FIG. 13. (Color online) Results from Monte Carlo simulations investigating the influence of surface recombination of radicals during plasma-assisted ALD (Ref. 304). (a) Equivalent thickness profile in a trench of aspect ratio 10 for different deposition regimes, obtained for various combinations of values for the sticking probability,  $s$ , and surface recombination probability,  $r$ . The positions within the trench labeled 0 and  $100\%$  correspond to the trench opening and trench bottom, respectively. Note that both recombination-limited cases show almost perfect overlap. (b) The dose required to reach saturation in trenches with aspect ratios of 10 and 30 for nonzero values of  $r$ . This dose is normalized to the dose required to reach saturation in these trenches when  $r = 0$ . For the simulations  $s = 0.01$  was assumed. From H.C.M. Knoops et al., J. Electrochem. Soc. 157, G241 (2010). Reproduced with permission of ECS—The Electrochemical Society.

Thickness profiles across a trench reveal how different growth regimes—reaction-limited, diffusion-limited, and recombination-limited—affect uniformity, with     recombination-limited cases showing more variation along the depth.

The dose necessary for saturation increases with higher surface recombination probability, and this effect becomes more pronounced at higher aspect ratios (AR = 30).

| Distance into Trench (%) | Reaction-limited (s = 0.01; r = 0) | Diffusion-limited (s = 1; r = 0) | Recombination-limited (s = 0.01; r = 0.9) | Recombination-limited (s = 1; r = 0.9) |
|--------------------------|------------------------------------|----------------------------------|-------------------------------------------|----------------------------------------|
| 0                        | 100                                | 100                              | 100                                       | 100                                    |
| 20                       | 98                                 | 100                              | 95                                        | 97                                     |
| 40                       | 95                                 | 99                               | 90                                        | 93                                     |
| 60                       | 92                                 | 98                               | 88                                        | 91                                     |
| 80                       | 90                                 | 98                               | 86                                        | 90                                     |
| 100                      | 92                                 | 99                               | 88                                        | 92                                     |

| Surface Recombination Probability (r) | Dose Necessary for Saturation (Aspect Ratio = 10) | Dose Necessary for Saturation (Aspect Ratio = 30) |
|---------------------------------------|---------------------------------------------------|---------------------------------------------------|
| 0.00                                  | 1                                                 | 1                                                 |
| 0.05                                  | 3                                                 | 10                                                |
| 0.10                                  | 6                                                 | 25                                                |
| 0.15                                  | 10                                                | 50                                                |
| 0.20                                  | 20                                                | 70                                                |
| 0.25                                  | 40                                                | 85                                                |
| 0.30                                  | 60                                                | 100                                               |

Answer: Surface recombination probability (r), Aspect ratio of the structure

Answer: Thickness remains nearly uniform for diffusion-limited and reaction-limited processes but decreases notably deeper into the trench for recombination-limited conditions, indicating non-uniform film growth.

Answer: Film thickness (%) as a function of trench depth.

Answer: Yes

icdar2026-competition-data/test/gold_standard_test_set/atomic-layer-deposition/experimental-usecase/10/H. B. Profijt et al.pdf


FIG. 14. (Color online) Experiments proving that VUV radiation from the plasma affects the surface passivation of crystalline Si by  $\mathrm{Al}_2\mathrm{O}_3$  when deposited by plasma-assisted ALD (Refs. 43, 303). After annealing, the wafers were exposed to an  $\mathrm{O_2}$  plasma for various exposure times. (a) The effective charge carrier lifetimes degraded for increasing exposure times at a rate which increased with increasing VUV radiation present in the plasma (higher intensity for higher power and/or lower pressure). (b) Results are also given for the situation in which the substrate is covered by quartz and  $\mathrm{MgF_2}$  windows that respectively block and do not block the VUV photons of  $9.5\mathrm{eV}$ . From H.B. Profijt et al., ECS Trans. 33, 61 (2010). Reproduced with permission of ECS—The Electrochemical Society.

Increasing plasma power accelerates carrier lifetime reduction, with 500 W exposure causing rapid degradation compared to 100 W.

The use of different chamber windows (no window, quartz, MgF₂) alters the plasma interaction with the surface, showing that optical transparency and window material strongly influence degradation rates.

| O₂ Plasma Exposure Time (s) | 100 W, 7.5 mTorr | 500 W, 7.5 mTorr | 100 W, 7.5 mTorr (quartz window) |
|----------------------------|------------------|------------------|----------------------------------|
| 0                          | 10.0             | 9.8              | 10.0                             |
| 25                         | 6.5              | 4.5              | 9.5                              |
| 50                         | 2.0              | 1.0              | 9.0                              |
| 75                         | 0.9              | 0.6              | 8.5                              |
| 100                        | 0.5              | 0.3              | 8.0                              |
| 125                        | 0.3              | 0.2              | 7.5                              |
| 150                        | 0.2              | 0.1              | 7.0                              |

Answer: Effective carrier lifetime (ms).

Answer: Yes

Answer: The effective carrier lifetime decreases exponentially with increasing O₂ plasma exposure time, with higher plasma power or direct exposure (no window) causing faster degradation.

Answer: Plasma power (100 W and 500 W), Pressure (7.5 mTorr),  Window material (none, quartz, MgF₂)


FIG. 16. Barrier failure temperatures for TaN and Ta films deposited by PVD and plasma-assisted ALD (Refs. 204, 219). After deposition the TaN and Ta layers were capped by  $200 \mathrm{nm}$  thick Cu films using the PVD technique. Barrier failure temperatures were determined by monitoring the disappearance of the Cu (111) peak by X-ray diffraction measurements. The ALD films were deposited using an  $\mathrm{H}_2 / \mathrm{N}_2$  plasma film in TaN and an  $\mathrm{H}_2$  plasma for Ta. From H. Kim et al., J. Appl. Phys. 95, 5848 (2004). Reprinted with permission. Copyright 2004, American Institute of Physics.

The figure shows how the failure temperature increases with film thickness for PE-ALD and PVD TaN and Ta films. Across all materials, thicker films withstand higher temperatures, with ALD-based films generally exhibiting higher thermal stability than their PVD counterparts.

| Film thickness (nm) | PE-ALD TaN | PVD TaN | PE-ALD Ta | PVD Ta |
|---|---|---|---|---|
| 0 | 580 | 590 | 600 | 610 |
| 5 | 670 | 680 | 690 | 700 |
| 10 | 760 | 770 | 780 | 790 |
| 15 | 850 | 860 | 870 | 880 |

Answer: Failure temperature increases with film thickness for all materials, with PE-ALD films exhibiting higher stability compared to PVD films across the measured range.

Answer: Failure temperature (°C).

Answer: (PE-ALD) TaN, (PVD), TaN

Answer: Yes


Fig. 4. (Color online) Ion energy distribution as measured by a retarding field energy analyzer (RFEA) in  $\mathrm{O}_2$ ,  $\mathrm{H}_2$  and  $\mathrm{N}_2$  plasmas (operating pressure: 8 mTorr; plasma power: 100 W) used for remote plasma-assisted ALD. The RFEA was positioned at the substrate stage. Measurements were performed in the home-built ALD-I reactor installed at Eindhoven University of Technology. Due to non-ideal effects such as capacitive coupling, the ion energies measured are higher than those measured in the Oxford Instruments FlexAL reactor, which are reported elsewhere (Ref. 303).

The figure presents ion energy distribution curves for O₂, H₂, and N₂ plasmas. Each plasma type exhibits a peak in ion energy distribution near 30–35 eV, with the H₂ plasma showing the highest intensity, O₂ plasma a moderate peak, and N₂ plasma the lowest distribution. This comparison highlights differences in ion energetics between the three plasma environments.

| Ion Energy (eV) | O₂ Plasma (a.u.) | H₂ Plasma (a.u.) | N₂ Plasma (a.u.) |
|-----------------|------------------|------------------|------------------|
| 0               | 0.00             | 0.00             | 0.00             |
| 10              | 0.05             | 0.10             | 0.00             |
| 20              | 0.30             | 0.40             | 0.10             |
| 25              | 0.60             | 0.80             | 0.20             |
| 30              | 0.90             | 1.00             | 0.30             |
| 35              | 0.80             | 0.70             | 0.20             |
| 40              | 0.20             | 0.20             | 0.10             |
| 50              | 0.00             | 0.00             | 0.00             |
| 60              | 0.00             | 0.00             | 0.00             |

Answer: The H₂ plasma shows the highest ion energy distribution peak around 30–35 eV, followed by O₂ plasma with a moderate peak and N₂ plasma with the lowest intensity.

Answer: Ion energy distribution (arbitrary units.)

Answer: H₂ plasma high energy, O₂ moderate, N₂ low energy and ion impact

Answer: Yes


FiG. 8. (Color online) Growth per cycle of  $\mathrm{Al}_2\mathrm{O}_3$  films as a function of the substrate temperature. The films were deposited by plasma-assisted ALD ( $\mathrm{O}_2$  plasma) and thermal ALD ( $\mathrm{H}_2\mathrm{O}$ ). Two different ALD reactors were used; one operating at  $15\mathrm{mTorr}$  and the other at  $170\mathrm{mTorr}$  (Refs. 43, 323). From S.E. Potts et al., J. Electrochem. Soc. 157, P66 (2010). Reproduced by permission of ECS—The Electrochemical Society.

The multiple line chart compares growth per cycle as a function of deposition temperature for both O₂ plasma and thermal (H₂O) ALD processes under two pressure conditions (15 mTorr and 170 mTorr). Growth per cycle decreases with temperature for plasma processes, while remaining nearly constant for thermal ALD. Higher pressure generally results in slightly higher growth rates.

| Deposition Temperature (°C) | O₂ Plasma (170 mTorr) | O₂ Plasma (15 mTorr) | Thermal (H₂O, 170 mTorr) | Thermal (H₂O, 15 mTorr) |
|-----------------------------|----------------------|----------------------|---------------------------|--------------------------|
| 50                          | 1.7                  | 1.6                  | 0.8                       | 0.7                      |
| 100                         | 1.6                  | 1.5                  | 0.8                       | 0.8                      |
| 150                         | 1.4                  | 1.3                  | 0.9                       | 0.9                      |
| 200                         | 1.2                  | 1.1                  | 0.9                       | 0.9                      |
| 250                         | 1.1                  | 1.0                  | 0.9                       | 0.9                      |
| 300                         | 1.0                  | 0.9                  | 0.9                       | 0.9                      |
| 350                         | 0.9                  | 0.8                  | 0.9                       | 0.9                      |
| 400                         | 0.8                  | 0.7                  | 0.9                       | 0.9                      |

Answer: The growth per cycle decreases with temperature for O₂ plasma ALD but remains almost constant for thermal (H₂O) ALD, indicating that plasma-based processes are more temperature-sensitive.

Answer: O₂ plasma 170 mTorr, O₂ plasma 15 mTorr, H₂O thermal 170 mTorr, H₂O thermal 15 mTorr

Answer: Yes

Answer: Growth per cycle (Å/cycle).


FiG. 9. (Color online) Growth per cycle of  $\mathrm{TiO}_2$  films as a function of the substrate temperature. Plasma-assisted ALD was carried out using  $\mathrm{Ti(O^iPr)_4}$ ,  $\mathrm{Ti(Cp^Me)(O^iPr)_3}$ ,  $\mathrm{Ti(Cp^*)OMe)_3}$ , and  $\mathrm{Ti(Cp^Me)(NMe_2)_3}$  as precursors in combination with an  $\mathrm{O}_2$  plasma (Refs. 56, 248). Data for thermal ALD with  $\mathrm{H}_2\mathrm{O}$  (Ref. 325) and  $\mathrm{O}_3$  (Ref. 324) using the widely employed  $\mathrm{Ti(O^iPr)_4}$  precursor are given for comparison. From S.E. Potts et al., J. Electrochem. Soc. 157, P66 (2010). Reproduced by permission of ECS—The Electrochemical Society.

The multiple line chart compares growth per cycle for several titanium precursors under both plasma and thermal ALD conditions. Plasma ALD processes, using precursors such as Ti(OPr)₄ and Ti(Cp*) derivatives, maintain higher and more stable growth rates across all temperatures, while thermal ALD processes show minimal growth and stronger temperature dependence.

| Deposition Temperature (°C) | Ti(OPr)₄ (Plasma) | Ti(Cp*)Y(OPr)₄ (Plasma) | Ti(Cp*)Y(OMe)₄ (Plasma) | Ti(Cp*)X(NMe₂)₃ (Plasma) | Ti(OPr)₄ + H₂O (Thermal) | Ti(OPr)₄ + O₃ (Thermal) |
|-----------------------------|-------------------|--------------------------|--------------------------|---------------------------|---------------------------|--------------------------|
| 50                          | 0.65              | 0.72                     | 0.68                     | 1.10                      | 0.05                      | 0.12                     |
| 100                         | 0.64              | 0.70                     | 0.67                     | 1.08                      | 0.04                      | 0.11                     |
| 150                         | 0.63              | 0.68                     | 0.65                     | 1.07                      | 0.03                      | 0.10                     |
| 200                         | 0.62              | 0.67                     | 0.64                     | 1.05                      | 0.03                      | 0.09                     |
| 250                         | 0.62              | 0.67                     | 0.64                     | 1.04                      | 0.03                      | 0.09                     |
| 300                         | 0.61              | 0.66                     | 0.63                     | 1.04                      | 0.02                      | 0.08                     |

Answer: Plasma ALD shows consistently higher and more stable growth per cycle across all deposition temperatures, while thermal ALD yields lower growth rates that decline further with temperature.

Answer: Deposition temperature.

Answer: Ti(OPr)₄ plasma, Ti(Cp*)Y(OPr)₄ plasma, Ti(Cp*)Y(OMe)₄ plasma, Ti(Cp*)X(NMe₂)₃ plasma, Ti(OPr)₄ + H₂O thermal, Ti(OPr)₄ + O₃ thermal.

Answer: Yes


FIG. 2. Normalized capacitance of BST films grown on  $\mathrm{MgO}$ $\mathrm{TiO_2 / Si}$  and  $\mathrm{Ta}_2\mathrm{O}_5 / \mathrm{Si}$  substrates.

The chart shows the normalized capacitance of BST films with different dielectric layers (BST/TiO2/Si, BST/Ta2O5/Si, BST/MgO) as a function of applied voltage. The tunability of capacitance is indicated at specific voltages.

| Applied Voltage (V) | Normalized Capacitance |
|---------------------|------------------------|
| 0                   | 1.0                    |
| 5                   | 0.7                    |
| 10                  | 0.4                    |
| 35                  | 0.6                    |

Answer: At an applied voltage of 10 V, the tunability values of BST films grown on Ta2O5/Si and TiO2 /Si were 53.1% and 72.9%, respectively and 20.7% for films on MgO single crystal substrate.

Answer: Improved tunability and, thus, higher frequency tuning agility, is possible with TiO2 or Ta2O5 buffer layers which increase the overall average dielectric constant and thereby minimize electric field attenuation

Answer: No

Answer:
BST films grown  on MgO single crystal substrates showed highly (100) preferred orientation and reached a tunability of only 41.6% with a much higher applied voltage of 35 V. The measured
capacitance of BST grown on TiO2/Si,Ta2O5 / Si, and MgO substrates at zero bias voltage was 125.8, 30.8, and 9.95 pF, respectively. In comparison to parallel-plate capacitors, coplanar designs generally require higher control voltages and
offer lower tunability, potential disadvantages of the IDC structure. The drive voltage needed to obtain appropriate tunability is very high in the BST/MgO structure given the low dielectric constant of the MgO single crystal substrate


Fig.1 Deposition rate of  $\mathrm{ZrO_2}$  thin films from the  $(\mathrm{CpMe})_2\mathrm{Zr(OMe)Me}$  and  $(\mathrm{CpMe})_2\mathrm{ZrMe}_2$  precursors and ozone as function of the deposition temperature. Pulsing times were  $1.0$  and  $2.0~\mathrm{s}$  for the  $\mathrm{Zr}$  precursor and  $\mathrm{O}_3$  respectively. Lines are guides to the eye.

The multiple line chart shows the deposition rate (Å/cycle) of  Zirconia (ZrO₂ ) thin films from two different zirconium precursors—(CpMe)₂Zr(OMe)Me and (CpMe)₂ZrMe₂—using O₃ as the oxidant, plotted against deposition temperature (250–500 °C).  The growth rate seems to increase with increase in temperature and the behaviours are slightly different for the two precursors.

| Deposition Temperature (°C) | Growth Rate (Å/cycle) | Process   |
|-----------------------------|------------------------|-----------------------------|
| 250                         | 0.24                   | (CpMe)₂Zr(OMe)Me / O₃       |
| 250                         | 0.21                   | (CpMe)₂ZrMe₂ / O₃           |
| 300                         | 0.56                   | (CpMe)₂Zr(OMe)Me / O₃       |
| 300                         | 0.52                   | (CpMe)₂ZrMe₂ / O₃           |
| 350                         | 0.64                   | (CpMe)₂Zr(OMe)Me / O₃       |
| 350                         | 0.56                   | (CpMe)₂ZrMe₂ / O₃           |
| 400                         | 0.75                   | (CpMe)₂Zr(OMe)Me / O₃       |
| 400                         | 0.58                   | (CpMe)₂ZrMe₂ / O₃           |
| 450                         | 0.88                   | (CpMe)₂Zr(OMe)Me / O₃       |
| 450                         | 0.71                   | (CpMe)₂ZrMe₂ / O₃           |
| 500                         | 1.10                   | (CpMe)₂Zr(OMe)Me / O₃       |
| 500                         | —                      | (CpMe)₂ZrMe₂ / O₃           |

Answer:
1. Precursors Used:

(CpMe)₂Zr(OMe)Me

(CpMe)₂ZrMe₂

2. Experimental Conditions for One ALD Cycle:

Zr Precursor Pulse Time: 1.0 s

O₃ (Oxidant) Pulse Time: 2.0 s

Deposition Temperature Range: 250–500 °C

Oxidant: O₃ (Ozone)

Answer: (CpMe)₂Zr(OMe)Me provides a stable, low deposition rate (~0.5 Å/cycle) from 250–400 °C, while (CpMe)₂ZrMe₂ only achieves a stable rate above 350 °C. The balance is between low-temperature capability and growth rate. Choosing the (OMe)Me precursor enables processing below 350 °C, but at the cost of a roughly 2x slower growth rate compared to the Me₂ precursor at its optimal temperature.

Answer: It reduces the deposition rate by approximately half (from ~1.0 Å/cycle to ~0.5 Å/cycle).

Answer: The (CpMe)₂Zr(OMe)Me precursor must be used, as it shows a stable rate at 300 °C. The consequence is a slower growth rate, which will increase the total deposition time per wafer to achieve the target film thickness. This reduces tool throughput and increases the cost of the manufacturing step.


Fig.2 Deposition rate of  $\mathrm{ZrO_2}$  thin films grown from  $(\mathrm{CpMe})_2\mathrm{Zr(OMe)Me}$  and  $(\mathrm{CpMe})_2\mathrm{ZrMe}_2$  as function of the  $\mathrm{Zr}$  precursor pulse length at the substrate temperatures indicated. Pulsing time was  $2.0~\mathrm{s}$  for  $\mathrm{O}_3$ . Lines are guides to the eye.

The multiple chart shows how the growth rate of ZrO₂ thin films changes with zirconium precursor pulse length for two precursors—(CpMe)₂Zr(OMe)Me and (CpMe)₂ZrMe₂—using O₃ as the oxidant. Measurements were taken at 400 °C and 350 °C. As the pulse length increases, the growth rate approaches saturation, but the two precursors show slightly different saturation behaviors. The O₃ pulse time was fixed at 2.0 s.

| Zr Precursor Pulse Length (s) | Growth Rate (Å/cycle) | Process                                      |
|-------------------------------|------------------------|-----------------------------------------------|
| 0.5                           | —                      | (CpMe)₂Zr(OMe)Me / O₃ at 400°C                |
| 0.5                           | —                      | (CpMe)₂Zr(OMe)Me / O₃ at 350°C                |
| 0.5                           | —                      | (CpMe)₂ZrMe₂ / O₃ at 350°C                           |
| 1.0                           | 0.72                   | (CpMe)₂Zr(OMe)Me / O₃ at 400°C                |
| 1.0                           | 0.60                   | (CpMe)₂Zr(OMe)Me / O₃ at 350°C                |
| 1.0                           | 0.52                   | (CpMe)₂ZrMe₂ / O₃ at 350°C                           |
| 1.5                           | 0.72                   | (CpMe)₂Zr(OMe)Me / O₃ at 400°C                |
| 1.5                           | 0.62                   | (CpMe)₂Zr(OMe)Me / O₃ at 350°C                |
| 1.5                           | —                       | (CpMe)₂ZrMe₂ / O₃ at 350°C                            |
| 2.0                           | 0.75                   | (CpMe)₂Zr(OMe)Me / O₃ at 400°C                |
| 2.0                           | 0.65                   | (CpMe)₂Zr(OMe)Me / O₃ at 350°C                |
| 2.0                           | 0.56                   | (CpMe)₂ZrMe₂ / O₃ at 350°C                          |
| 2.5                           | 0.75                   | (CpMe)₂Zr(OMe)Me / O₃ at 400°C                |
| 2.5                           | 0.65                   | (CpMe)₂Zr(OMe)Me / O₃ at 350°C                |
| 2.5                           | —                      | (CpMe)₂ZrMe₂ / O₃ at 350°C                           |
| 3.0                           | —                      | (CpMe)₂Zr(OMe)Me / O₃ at 400°C                |
| 3.0                           | 0.66                   | (CpMe)₂Zr(OMe)Me / O₃ at 350°C                |
| 3.0                           | 0.55                   | (CpMe)₂ZrMe₂ / O₃ at 350°C                         |
| 3.5                           | —                      | (CpMe)₂Zr(OMe)Me / O₃ at 400°C                |
| 3.5                           | —                      | (CpMe)₂Zr(OMe)Me / O₃ at 350°C                |
| 3.5                           | —                      | (CpMe)₂ZrMe₂ / O₃ at 350°C                           |
| 30                            | —                      | (CpMe)₂Zr(OMe)Me / O₃ at 400°C                |
| 30                            | 0.62                   | (CpMe)₂Zr(OMe)Me / O₃ at 350°C                |
| 30                            | 0.52                   | (CpMe)₂ZrMe₂ / O₃ at 350°C                          |

Answer:
Variable Zr precursor pulse (x s)

, Purge

, Fixed O₃ pulse (2.0 s)

, Purge

Answer: The (CpMe)₂Zr(OMe)Me precursor at 400°C reaches saturation with a shorter pulse length (~1.5 s) than the (CpMe)₂ZrMe₂ precursor at 350°C, which requires a longer pulse (~2.5 s) to saturate. This indicates the (OMe)Me precursor reacts and saturates the surface more rapidly at a higher temperature, while the Me₂ precursor has slower surface reaction kinetics at 350°C.

Answer: Replacing one -OMe ligand with a second -Me ligand.

Answer: (CpMe)₂Zr(OMe)Me at 350°C is preferable. It shows a clear, achievable saturation plateau at this temperature, ensuring self-limiting growth for uniformity. Using the Me₂ precursor at 350°C would require a longer, harder-to-control pulse to reach saturation, risking incomplete reactions and less uniform films.


Fig. 7 Current density-voltage (a) and Poole-Frenkel (b) plots of the current-voltage dependences measured on some representative  $\mathrm{ZrO_2}$  films deposited from precursors indicated by labels. Layer thicknesses are also given in the labels.

The muliple line chart shows Current Density-Voltage (J-V) plots  for ZrO₂ films of varying thickness (3.6–13.1 nm) deposited from two different precursors. The analysis identifies dominant leakage current mechanisms: Schottky emission (interface-limited) at lower fields.

The muliple line chart shows Poole-Frenkel plots for ZrO₂ films of varying thickness (3.6–13.1 nm) deposited from two different precursors. The analysis identifies dominant leakage current mechanisms: Poole-Frenkel emission (bulk trap-limited) at higher fields.

| Voltage, V | Current density, A/cm² |
|---|---|
| 0 | 10^-9 |
| 1 | 10^-8 |
| 2 | 10^-7 |
| 3 | 10^-6 |
| 4 | 10^-5 |
| 5 | 10^-4 |
| 6 | 10^-3 |
| 7 | 10^-2 |
| 8 | 10^-1 |

| E^(1/2), (MV/cm)^(1/2) | ln(J/E) |
|---|---|
| 0.0 | -20 |
| 0.5 | -15 |
| 1.0 | -10 |
| 1.5 | -5 |
| 2.0 | 0 |
| 2.5 | 5 |
| 3.0 | 10 |
| 3.5 | 15 |
| 4.0 | 20 |

Answer:
Deposit a top electrode (like Al/Ag/Au) to form a capacitor.

Apply a series of increasing voltage biases to the capacitor.

Measure the resulting current flowing through the film at each applied voltage.
The final critical step is measuring the current, which directly gives the leakage density (J) for that specific voltage (V), allowing the trace to be plotted.

Answer:
(CpMe)₂Zr(OMe)Me (3.9 nm): Pro: Lower leakage current (~10⁻⁷ A/cm² at 2V).

(CpMe)₂ZrMe₂ (3.6 nm): Con: Higher leakage current (~10⁻⁴ A/cm² at 2V).

(CpMe)₂Zr(OMe)Me precursor is better for low leakage.

Answer: The slope is proportional to the square root of the trap's dynamic dielectric constant and its energy depth. A steeper slope (like for the (CpMe)₂ZrMe₂ film) suggests a lower dynamic dielectric constant or different trap energetics. The OMe ligand in the (CpMe)₂Zr(OMe)Me precursor may incorporate oxygen differently, potentially passivating defects or creating a distinct trap distribution with a shallower effective energy level, leading to its different slope.

Answer: This implies that in thin films (3.9 nm), the dominant leakage mechanism shifts from bulk trap-assisted (Poole-Frenkel) to a different mechanism, most likely direct tunneling. Tunneling current is thickness-sensitive and can be high and unpredictable.For a capacitor requiring long-term charge retention, this makes very thin ZrO₂ films unreliable, as charge will leak rapidly via tunneling, regardless of improvements to bulk film quality.


Fig. 1 Composition of deposited films versus percentage of titanium oxide sub-cycles. Experimental data are compared with a model based on surface utilization10 and the growth rates of the individual binary oxides.

The chart shows the titanium concentration (at.% relative to total metal content) as a function of TiO₂ subcycles (%). It compares experimental data with theoretical values from a surface utilization model with calculated values from individual growth rates. The surface utilization model better predicts experimental values.

| TiO₂ subcycles (%) | Titanium concentration (at.%): Experimental data | Titanium concentration (at.%): from surface utilization model | Titanium concentration (at.%): calculated from individual growth rates |
|---|---|---|---|
| 0.0   | 0.0 | 0.0  | 0.0   |
| 5.8   | 47.2 | 25.3  | 13.5  |
| 10.9  | 58.1 | 40.3  | 23.3  |
| 13.8  | 62.5 | 47.4  | 29.0  |
| 17.0  | 62.4 | 52.8  | 32.9  |
| 19.8  | 63.0 | 57.7  | 37.7  |
| 25.0  | 68.7 | 64.6  | 45.3  |
| 29.8  | 77.5 | 70.3  | 51.0  |
| 32.8  | 76.5 | 73.2  | 54.5  |
| 50.2  | 84.6 | 84.5  | 71.2  |
| 67.2  | 93.5 | 92.0  | 83.3  |
| 75.2  | 94.2 | 94.5  | 88.3  |
| 100 | 100  | 100  | 100  |

Answer: Surface utilization model.

Answer: The calculations generally underestimate the experimental values.

Answer: Approx. 5-6%.

Answer: All three datasets intersect at 100% TiO₂ subcycles, which corresponds to 100 at.% Ti. It is physically necessary for all methods to reach this value because at 100% subcycles, the deposition consists exclusively of titanium precursor pulses. Therefore, the resulting film is pure titanium oxide, physically forcing the cation composition to be 100% titanium.


Fig. 3 Growth per cycle as a function of the percentage of  $\mathrm{TiO_2}$  subcycles.

The chart shows the growth per cycle (Å/cycle) as a function of the percentage of TiO₂ subcycles. It compares theoretical values derived from the individual growth rates (open circles) with experimental values calculated from film thicknesses measured by X-ray Reflectivity (solid squares). Experimental growth rates are consistently lower than the prediction.

| TiO₂ subcycles (%) | Growth per cycle (Å/cycle): calculated from individual growth rates | Growth per cycle (Å/cycle): calculated from XRR thickness |
|---|---|---|
| 0   | 0.280 | 0.280 |
| 6   | 0.293 | 0.250 |
| 12  | 0.306 | 0.178 |
| 14  | 0.313 | 0.180 |
| 18  | 0.320 | 0.239 |
| 20  | 0.326 | 0.260 |
| 25  | 0.338 | 0.278 |
| 33  | 0.357 | 0.239 |
| 50  | 0.399 | 0.300 |
| 67  | 0.440 | 0.359 |
| 75  | 0.459 | 0.379 |
| 100 | 0.519 | 0.519 |

Answer: Approx. 0.519 Å/cycle (100% TiO₂ subcycles).

Answer: Approx. 0.28 Å/cycle (0% TiO₂ subcycles).

Answer: Theoretical values overestimate the experimental ones (derived from XRR measurement).

Answer: Theoretical values calculated from individual growth rates.


Fig. 6 SIMS depth profiles of LLT films grown with  $\mathrm{LiO}^{\prime}\mathrm{Bu}$  pulse times of 2, 8, and  $12\mathrm{s}$ .

The  chart displays SIMS depth profiles showing the distribution of Ti-48, Li-6 and  La-138 throughout the thickness of the film in nanometers for films grown with different precursor pulse times (12, 8, 2 s).

| Species | Pulse time (s) | Depth (nm) | Intensity (counts/second) |
|---|---|---|---|
| La-138 | 12 | 2.85 | 240 |
| La-138 | 12 | 20.4| 369 |
| La-138 | 12 | 95.1| 376 |
| La-138 | 12 | 111.45| 779 |
| La-138 | 12 | 128.7 | 87 |
| La-138  | 8 | 2.85 | 241 |
| La-138  | 8 | 18.9 | 362 |
| La-138  | 8 | 83.7 |376 |
| La-138  | 8 | 96.3 | 867 |
| La-138  | 8 | 115.05 | 72 |
| La-138  | 2 | 2.85 | 241 |
| La-138  | 2 | 18.9  | 362 |
| La-138  | 2 | 71.85 | 389 |
| La-138  | 2 | 79.8  | 499 |
| La-138  | 2 | 95.85 | 71 |
| Li-6  | 12 | 0.89  |   3869268  |
| Li-6  | 12 | 5.7 |  448809  |
| Li-6  | 12 | 91.35 |  490593  |
| Li-6  | 12 | 94.95 |  851946  |
| Li-6  | 12 | 102.3 |  349796  |
| Li-6  | 12 | 108.45 |  481936  |
| Li-6  | 12 | 127.2 |  42045  |
| Li-6  | 8 | 3.15 |  481936 |
| Li-6  | 8 | 79.35 | 481936 |
| Li-6  | 8 | 84.75 | 882828 |
| Li-6  | 8 | 89.4 | 282508 |
| Li-6  | 8 | 95.4 | 481936 |
| Li-6  | 8 | 123.15 | 7748 |
| Li-6  | 2 | 0.75 |  1402514 |
| Li-6  | 2 | 8.25 |  228164 |
| Li-6  | 2 | 60.75 |  382362 |
| Li-6  | 2 | 68.4 |  675923 |
| Li-6  | 2 | 75 |  362475 |
| Li-6  | 2 | 123.159 |  7748 |
| Li-6  | 2 | 79.2 |  490593 |
| Li-6  | 2 | 103 |  14448 |
| Ti-48  | 12 | 2.1 | 7215184 |
| Ti-48  | 12 | 5.25 | 8933691 |
| Ti-48  | 12 | 104.1 | 5931928 |
| Ti-48  | 12 | 128.7 | 75659.94 |
| Ti-48  | 8 | 2.1 | 8621186 |
| Ti-48  | 8 | 4.95 | 9940831 |
| Ti-48  | 8 | 90.6 | 4876905 |
| Ti-48  | 8 | 123.6 | 8029 |
| Ti-48  | 2 | 2.1 |8621186 |
| Ti-48  | 2 | 4.95 | 9940831 |
| Ti-48  | 2 | 74.55 | 5524183 |
| Ti-48  | 2 | 103.95 | 14971 |

Answer: The film grown with 12 s pulse.

Answer: No. The lithium signal curve after 2 s is distinctly lower in intensity compared to the curves at 8 s and 12 s. Since the 2 s curve is below the maximum level, it indicates that the maximum possible amount of lithium has not been incorporated yet.

Answer: Ti-48, Li-6, La-138

Answer: No. The signal intensities for all three isotopes drop by orders of magnitude once the depth passes the film thickness (e.g. for >120 nm for the 12s sample). This indicates the substrate is a different material.


Fig. 7 SIMS depth profiles of lithium, titanium, and lanthanum in the LLT films with one and three  $\mathrm{LiO}^{\prime}\mathrm{Bu}+$  water sub-cycles.

The chart displays SIMS depth profiles comparing the intensity at various depths for isotopes of titanium (Ti-48), lithium (Li-6), and lanthanum (La-138) for films grown using one lithium precursor sub-cycle and three lithium sub-cycles.

| Species | Number of lithium sub-cycles | Depth (nm) | Intensity (counts/second) |
|---|---|---|---|
| La-138 | 3 Li sub-cycles | 3 | 272 |
| La-138 | 3 Li sub-cycles | 128 | 372 |
| La-138 | 3 Li sub-cycles | 134 | 469 |
| La-138 | 3 Li sub-cycles | 159 |  165 |
| La-138 | 1 Li sub-cycle | 3 | 273 |
| La-138 | 1 Li sub-cycle | 84 | 379 |
| La-138 | 1 Li sub-cycle | 97 |  925 |
| La-138 | 1 Li sub-cycle | 115 |  83 |
| Li-6 | 3 Li sub-cycles | 0.6 |  2173095 |
| Li-6 | 3 Li sub-cycles | 3.6 | 478382 |
| Li-6 | 3 Li sub-cycles | 55 |  527121 |
| Li-6 | 3 Li sub-cycles | 78 | 1474142 |
| Li-6 | 3 Li sub-cycles | 158 |  158284 |
| Li-6 | 1 Li sub-cycle | 0.6 | 2173095 |
| Li-6 | 1 Li sub-cycle | 7.4 |  357578 |
| Li-6 | 1 Li sub-cycle | 78 |  497312 |
| Li-6 | 1 Li sub-cycle | 84 |  823627 |
| Li-6 | 1 Li sub-cycle | 90 | 294511 |
| Li-6 | 1 Li sub-cycle | 95 |  478382 |
| Li-6 | 1 Li sub-cycle | 124 | 7237 |
| Ti - 48 | 3 Li sub-cycles | 2.2 | 7097797 |
| Ti - 48 | 3 Li sub-cycles | 4.4 | 8130408 |
| Ti - 48 | 3 Li sub-cycles | 115 |  5733594 |
| Ti - 48 | 3 Li sub-cycles | 151 |  442657 |
| Ti - 48 | 3 Li sub-cycles | 1597 | 330874 |
| Ti - 48 | 1 Li sub-cycle | 2.2 | 7097797 |
| Ti - 48 | 1 Li sub-cycle | 5.2 | 9495724 |
| Ti - 48 | 1 Li sub-cycle | 88 | 4909206 |
| Ti - 48 | 1 Li sub-cycle | 123 |  7379 |

Answer: The one grown with 3 lithium sub-cycles.

Answer: No.  Between 60 nm and 120 nm there is a broad surge in intensity. While the upper region (10–60 nm) overlaps with the 1-sub-cycle reference, suggesting normal growth, the massive surge in intensity near the bottom might indicate that excess lithium from the additional pulses migrated and segregated at the interface.

Answer: The film grown with one lithium precursor pulse.

Answer: At the interface, as indicated by the surge in intensity at approx. 80 nm.


Fig. 3 (a) In situ thickness measurements by SE for plasma-assisted ALD of  $\mathrm{Li}_{2}\mathrm{CO}_{3}$  at 50, 200, 275 and  $300^{\circ}\mathrm{C}$  and thermal ALD of  $\mathrm{Li}_{2}\mathrm{CO}_{3}$  at  $150^{\circ}\mathrm{C}$ . The film growth between 50 and  $200^{\circ}\mathrm{C}$  with plasma ALD was very similar (see ESI†). (b) Growth per cycle as a function of process table temperature for both plasma-assisted (squares) and thermal (circles) ALD processes.

The chart plots the thickness of a material as a function of the number of cycles for different thermal and plasma treatments at various temperatures.

The chart plots the GPC SE and GPC EBS values against temperature for both thermal and plasma treatments.

| Number of Cycles | Thermal 150 °C | Plasma 50 °C | Plasma 200 °C | Plasma 275 °C | Plasma 300 °C |
|-------------------|-----------------|--------------|---------------|---------------|---------------|
| 0                | 0               | 0            | 0             | 0             | 0             |
| 100              | 8               | 10           | 15            | 18            | 20            |
| 200              | 15              | 18           | 25            | 28            | 30            |
| 300              | 22              | 25           | 32            | 36            | 38            |
| 400              | 28              | 32           | 38            | 42            | 45            |
| 500              | 35              | 38           | 44            | 48            | 50            |
| 600              | 42              | 45           | 50            | 54            | 58            |

| Temperature (°C) | GPC SE Thermal (Å) | GPC SE Plasma (Å) | GPC EBS Thermal (Li.at.nm⁻²) | GPC EBS Plasma (Li.at.nm⁻²) |
|-------------------|----------------------|---------------------|--------------------------------|--------------------------------|
| 50               | 0.3                  | 0.8                 | -                            | -                            |
| 100              | 0.6                  | 0.8                 | -                              | -                              |
| 150              | 0.5                  | 0.8                 | 3                              | 4                              |
| 200              | 0.5                  | 0.8                 | 3                              | 4                              |
| 275              | 0.5                  | 0.8                 | 3                              | 4                              |
| 300              | 0.5                  | 1.6                 | 3                              | 7                              |

Answer: For plasma-assisted ALD and Tsub </=200 °C, the thickness of the films develops linearly with the number of cycles. For temperatures higher than 250 °C, the film thickness develops according to two slopes, which correlates with a transition in film chemical composition

Answer: Yes

Answer: It can be noticed that the growth per cycle of the thermal ALD process strongly decreases at 50 °C, indicating the lower limit of the temperature window. The ALD process window for the plasma-assisted process is extended towards lower temperatures, as it has a similar growth per cycle at 50 °C as at higher temperatures

Answer: The overall growth per cycle is higher for the plasma-assisted process as compared to the thermal process. This is more ofen observed for plasma processes due to the relatively high reactivity of the plasma species which could create a higher density of reactive surface sites


FIG. 2. (Color online) Thickness of  $\mathrm{Al}_2\mathrm{O}_3$  as a function of the number of cycles as measured by SE for deposition temperatures of 70 and  $200^{\circ}\mathrm{C}$ . The data shown are for films deposited on plasma oxidized  $c$ -Si substrates.

The line chart shows the relationship between the number of cycles and the SE thickness at two different temperatures, 70 °C and 200 °C.

| Number of cycles | SE: Thickness (Å) 70 °C | SE: Thickness (Å) 200 °C |
|---|---|---|
| 0 | 0 | 0 |
| 50 | 60 | 60 |
| 100 | 160 | 120 |
| 150 | 250 | 180 |
| 200 | 340 | 250 |
| 250 | 420 | 320 |
| 300 | 500 | 380 |

Answer: Plasma oxidized Si.

Answer: 70 and 200 °C.

Answer: 1.66 Å/cycle.

Answer: 1.27 Å/cycle.


FIG. 9. (Color online) Time-resolved OES measurements at the wavelengths of 519, 656, and  $777~\mathrm{nm}$  corresponding to  $\mathrm{CO^{*}}$ $\mathrm{H^{*}}$  and  $\mathrm{O^{*}}$  respectively. (a) Emission for an  $\mathrm{O}_2$  plasma without preceding  $\mathrm{Al(CH_3)_3}$  dosing and (b) the emission for a plasma exposure step during an ALD cycle.

The line chart displays the intensity of OES (Optical Emission Spectroscopy) during O2 plasma exposure with preceding Al(CH3)3 dosing.

The line chart shows the intensity of OES during O2 plasma exposure during an ALD cycle step.

| Time (s) | Intensity (a.u.) 777 nm - O* | Intensity (a.u.) 656 nm - H* | Intensity (a.u.) 519 nm - CO* |
|---|---|---|---|
| 0 | 0 | 0 | 0 |
| 1 | 60 | 0 | 0 |
| 2 | 60 | 0 | 0 |

| Time (s) | Intensity (a.u.) 777 nm - O* | Intensity (a.u.) 656 nm - H* | Intensity (a.u.) 519 nm - CO* |
|---|---|---|---|
| 0 | 0 | 0 | 0 |
| 0.5 | 40 | 80 | 140 |
| 1 | 60 | 10 | 20 |
| 1.5 | 60 | 0 | 10 |
| 2 | 60 | 0 | 10 |

Answer: 519 nm (CO*), 656 nm (H*), 777 nm (O*)

Answer: In a pure O₂ plasma strike, a stable O* emission at 777 nm appears immediately, while no significant emission is observed at 519 or 656 nm. During an ALD-cycle plasma strike, strong initial emissions at 519 and 656 nm are observed, reflecting the formation of reaction products such as CO, CO₂, and H₂O.

Answer: The surface reactions occur on the time scale of 1 second.

Answer: When the plasma is ignited after an aluminium precursor dose, transient increases in CO* and H* emission are observed, indicating the formation of gas-phase reaction products such as CO, CO₂, and H₂O. Simultaneously, the O* emission is initially suppressed, reflecting the consumption of oxygen radicals in surface oxidation and by-product formation. As the surface reactions approach saturation, the emissions associated with reaction products decay due to pumping and reduced reactant availability, while the O* emission recovers to the level seen in a pure O₂ plasma. The short decay time of these signals shows that reaction completion occurs well within one second, consistent with independent spectroscopic ellipsometry results demonstrating saturated growth for plasma exposure times of half a second or longer.


FIG. 2. (Color online) (a) Film thickness as a function of number of ALD cycles with temperature ranging between 150 and  $400^{\circ}\mathrm{C}$ . The thickness values have been obtained from in situ SE. (b) GPC values corresponding to the studied substrate stage temperatures and the average number of Hf atoms deposited per ALD cycle as determined from RBS measurements.

The figure shows the thickness of a material as a function of ALD cycles at various temperatures (150–400 °C). For all temperatures, the thickness increases linearly with cycle count.

The figure compares the growth per cycle (GPC) and the number of Hf atoms per cycle at different temperatures (150–400 °C). The Hf atoms per cycle show a small increase at higher temperatures; GPC stays relatively constant.

| ALD cycles | 150°C : Thinkness (nm)| 200°C: Thinkness (nm) | 250°C: Thinkness (nm) | 300°C: Thinkness (nm) | 350°C: Thinkness (nm) | 400°C: Thinkness (nm) |
|---|---|---|---|---|---|---|
| 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 100 | 11 | 10| 10 | 9.9 | 9.76 | 9.3 |
| 200 | 22 | 22 | 21 | 20.9 | 20.5 | 20.4 |
| 300 | 34 | 33 | 32 | 31.8 | 32 | 31.8 |

| Table temperature (°C) | GPC (nm) | Hf atoms per cycle (nm²) |
|---|---|---|
| 150 | 0.113 ± 0.008 | - |
| 200 | 0.111 ± 0.008 | 2.71 ± 0.01 |
| 250 | 0.108 ± 0.008 | - |
| 300 | 0.106 ± 0.008 | 2.77 ± 0.01 |
| 350 | 0.107 ± 0.008 | - |
| 400 | 0.109 ± 0.008 | 2.91 ± 0.01 |

Answer: At lower temeperatures.

Answer: The GPC stays nearly constant (~0.11 nm/cycle) across temperature, but the Hf atoms incorporated per cycle are lower at the lower temperatures and rise as temperature increases. If the film grows by about the same thickness per cycle but contains fewer Hf atoms per cycle, the added volume must include a larger fraction of non-Hf species. This mismatch supports the inference of greater impurity incorporation (or reduced film density) at lower temperatures.

Answer: They correlate positively.

Answer: From about 150 to 400 °C.


Fig. 10 Bright IV curves of SHJ cells with  $10\mathrm{nmMoO}_x$

The chart displays the relationship between voltage and current density for three different plasma times and/or compositions.

| voltage (V) | 10.6% 2 second O2 | 10.4% 2 second O2 & Ar | 7.3% 1 second O2 |
|---|---|---|---|
|-0.2 | -30 | -30 | -30 |
| 0 | -30 | -30 | -30 |
| 0.2 | -30 | -30 | -30 |
| 0.4 | -25 | -25 | -5 |
| 0.6 | 0 | 0 | 0 |
| 0.8 | 15 | 15 | 5 |

Answer: No

Answer: Around 0.65 V.

Answer: 10 nm.

Answer: About 10 mA/cm^2.


Fig. 11 Bright IV curves of SHJ cells with  $20 \mathrm{nm} \mathrm{MoO}_x$

IV curve of three samples, all with different plasma exposure times and/or compositions. The tested solar cells had a MnOx thickness of 20 nm.

| voltage (V) | 9.0% 2 second O2 | 10.4% 2 second O2 & Ar | 5.8% 1 second O2 |
|---|---|---|---|
|-0.2 | -30 | -30 | -30 |
| 0 | -30 | -30 | -30 |
| 0.2 | -30 | -30 | -28 |
| 0.4 | -20 | -24 | -2 |
| 0.6 | 0 | 0 | 0 |
| 0.8 | 18 | 6 | 8 |

Answer: 20 nm.

Answer: The current decreases in all produced solar cells when the oxide layer thickness is doubled.

Answer: Because their lower initial oxygen content can lead to a reduced MoOx work function after ITO sputtering and annealing, increasing the hole transport barrier and worsening VOC and fill factor.

Answer: A pronounced s-shape in the illuminated IV curves limits the fill factor and efficiency.


Figure 2. (a) Amount of hydrogen and carbon impurities in  $40\mathrm{nm}\mathrm{Li}_3\mathrm{PO}_4$  layers deposited at different processing temperatures as determined by ERD. A clear increase of the amount of incorporated hydrogen is seen on reducing the temperature. (b) Shows the dependency of the Li-ion conductivity, as determined by impedance spectroscopy, on the processing temperature. A strong rise in conductivity is seen when reducing the processing temperature, attributed to the reduced crystallinity of the layers.

The line chart shows the atomic percentage of hydrogen (H Content) and carbon (C Content) as a function of processing temperature. The atomic percentage of H decreases as the processing temperature increases, while the atomic percentage of C remains almost constant.

The line chart illustrates the change in conductivity (Cond) with respect to processing temperature. The Li-ion conductivity decreases as the processing temperature increases.

| Processing T (°C) | H content | C content |
| --- | --- | --- |
| 200 | 14 | 2 |
| 250 | 12 | 2.2 |
| 278 | 10 | 2 |

| Processing T (°C) | Cond (nS/cm) |
|---|---|
| 200 | 0.14 |
| 226 | 0.07 |
| 250 | 0.05 |
| 280 | 0.05 |

Answer: Li3PO4 films with a thickness of 40 nm.

Answer: The Li-ion conductivity decreases when the processing temperature increases.

Answer: The li-ion conductivity is highest at 200 °C.

Answer: The Li-ion conductivity decreases at higher temperatures due to increased crystallinity of the layers.


FIG. 1. (a) Optical emission signals during a 100 mTorr  $\mathbf{N}_2$  plasma exposure step following the precursor exposure in the cycle. A constant signal is observed for plasma feedstock species (here illustrated for  $\mathbf{N}_2^*$  emission at  $337\mathrm{nm}$ $(\mathrm{C}^3\prod_u\rightarrow \mathrm{B}^3\prod_g))$  , and a time-dependent signal is observed for dissociated reaction products (here illustrated for  $\mathbf{CN}^*$  emission at  $388\mathrm{nm}$ $(\mathrm{B}^2\Sigma \rightarrow X^2\Sigma))$  .14 Note that the emission fluctuation during the start-up of the plasma exposure can be assigned due to plasma matching effects which indicate the large influence of the released reaction products on the plasma composition. (b) Schematic illustration of the redeposition process. During the plasma exposure step, precursor ligands are liberated from the surface and enter the gas phase. These reaction products can dissociate in the plasma (e.g., the electron impact) leading to reactive species which can redeposit on the surface. The extent of the redeposition will depend on the gas residence time  $\tau$

The line chart the optical emission signal over time, for two distinct peaks at 337 nm and 388 nm related to plasma feedstock species and reaction products.

The apparatus diagram depicts the flow of feedstock gas through a plasma reactor, showing the movement of feedstock species, reaction products, and redepositing species.

| Time (s) | Optical emission signal (a.u.) plasma feedstock|Optical emission signal (a.u.) reaction products|
|---|---|---|
| 1 | 0|0|
|1.5|3|1|
| 2 | 3|0.5|
| 3 | 3|0|
| 4 |3|0|
| 5 | 3|0|

Answer: Due to the incorporation of other species in the plasma there is an effect of the matching of the plasma in the first second.

Answer: Carbon.

Answer: The reactor is a downstream plasma reactor, the gases come in from the top and are pump away from underneath the substrate.

Answer: The gas residence time can be reduced by increasing the flow into the reactor or by pumping faster.


FIG. 3. (a) Growth per cycle (GPC) as a function of  $\mathbb{N}_2$  plasma exposure time for  $\mathrm{SiN}_x$  films deposited at  $200^{\circ}\mathrm{C}$  and three different plasma gas residence times  $\tau = 0.44\mathrm{s}$  for  $100\mathrm{sccm}$ $\mathbf{N}_2$  at  $40\mathrm{mTorr}$ $\tau = 0.15\mathrm{s}$  for  $100\mathrm{sccm}$ $\mathrm{N}_2 + 200$  sccm Ar at  $40\mathrm{mTorr}$  and  $\tau = 0.09\mathrm{s}$  for  $100\mathrm{sccm}$ $\mathrm{N}_2 + 200$  sccm Ar at  $24\mathrm{mTorr}$ . The lines are fits to the expression given in (a). (b) The values of the time constants  $t_A$  and  $t_B$  extracted from the fits in (a) as a function of residence time  $\tau$ . The solid lines are linear fits to the data points.

The chart shows the growth per cycle (Å) over plasma exposure time (s) for different plasma gas residence times. The growth rate initially increases rapidly, reaches a peak and then gradually decreases for all conditions.

The chart displays the relationship between plasma gas residence time (s) and time constant (s). There is a linear increase in time constant B with increasing plasma gas residence time, whilst time constan A remains constant.

| Plasma exposure time (s) | Growth per cycle (Å) 0.44 s|Growth per cycle (Å) 0.15 s|Growth per cycle (Å) 0.09 s|
|---|---|---|---|
| 0 | 0.0 |0.0|0.0|
| 2 | 0.46 |0.31|0.27|
| 4 | 0.44 |0.29|0.26|
| 6 | 0.4 |0.26|0.25|
| 8 | 0.35 |0.25|0.25|
| 12 | 0.3 |0.24|0.24|
| 16 | 0.27 |0.24|0.24|

| Plasma gas residence time (s) | Time constant tB (s) | Time constant tA (s) |
|---|---|---|
| 0.0 | 0.0 |0.8|
| 0.1 | 2 ± 0.7 |0.8|
| 0.15 | 2.5 ± 0.3 |0.8|
| 0.45 | 8 ± 2 |0.8|

Answer: Usually a saturation curve is fitted with a single exponential like: GPC = A(1-e^(-t/tA)).

Answer: The height of the peak is related to the amount of redeposition of ligand species that come in to the plasma.

Answer: Longer plasma exposure times give lower GPC values indicating that the species resulting of redeposition are removed from the surface.

Answer: Only time constant B.


Figure 5. Arrhenius plot of  $\Gamma (T)$ ,  $k^{\mathrm{TST}}(T)$ , and  $k^{\mathrm{SC - TST}}(T)$  for the  $(\mathrm{SiH}_3\mathrm{O})_3\mathrm{Si - OH}^* + \mathrm{Ti}_4$  reaction.

Multi-line Arrhenius plot for the (SiH₃O)₃Si–OH* + TiI₄ reaction, showing temperature dependence of rate constants for the tunneling correction factor (¡), classical transition-state theory (kTST), and semiclassical tunneling-corrected rate constant (kSC-TST). At low temperatures, quantum tunneling dominates, with kSC-TST higher than kTST, while at high temperatures classical Arrhenius behavior is recovered. The crossover temperature (Tx ≈ 151 K) indicates where tunneling effects become negligible.

|Temperature (K)|¡|kTST (s⁻¹)|kSC-TST (s⁻¹)|
|---------------|--|----------|-------------|
|60.00|6.77|5.57 × 10⁻³⁶|3.77 × 10⁻⁶|
|90.00|1.99|1.55 × 10⁻¹⁹|3.10 × 10⁻⁶|
|120.00|2.58|1.86 × 10⁻¹¹|4.79 × 10⁻⁶|
|150.00|3.54|1.92 × 10⁻⁶|6.78 × 10⁻⁵|
|180.00|4.93|4.37 × 10⁻³|2.15 × 10⁻²|
|210.00|2.78|1.12 × 10⁰|3.11 × 10⁰|
|250.00|1.95|2.06 × 10²|4.01 × 10²|
|300.00|1.55|1.87 × 10⁴|2.91 × 10⁴|
|350.00|1.37|4.81 × 10⁵|6.59 × 10⁵|
|423.15|1.23|1.63 × 10⁷|2.01 × 10⁷|
|473.15|1.18|8.18 × 10⁷|9.67 × 10⁷|
|523.15|1.15|3.69 × 10⁸|4.23 × 10⁸|
|573.15|1.12|1.08 × 10⁹|1.21 × 10⁹|
|623.15|1.10|2.92 × 10⁹|3.22 × 10⁹|
|673.15|1.08|6.85 × 10⁹|7.42 × 10⁹|
|723.15|1.07|1.43 × 10¹⁰|1.54 × 10¹⁰|

Answer: Yes

Answer: At high temperatures, kSC-TST closely matches kTST, indicating tunneling effects are negligible in this regime.

Answer: The Arrhenius plot shows a clear crossover temperature (Tx ≈ 151 K) below which tunneling significantly increases the reaction rate. By analyzing this plot, one can determine the temperature range where classical TST underestimates the rate and tunneling must be considered. For practical ALD applications, this allows process engineers to predict whether tunneling effects can be ignored at typical operating temperatures, ensuring accurate rate estimates and proper design of deposition cycles.

Answer: ¡ (tunneling correction factor) – Indicates the contribution of quantum tunneling to the rate constant, kTST – Classical rate constant from transition-state theory without tunneling correction, kSC-TST – Semiclassical rate constant including tunneling effects

icdar2026-competition-data/test/gold_standard_test_set/atomic-layer-deposition/simulation-usecase/1/Zheng Hu et al.pdf


Figure 8. Arrhenius plot of the rate constants of the  $\mathrm{(SiH_3O)_3Si - OTi - }$ $\mathrm{I}_3^* +\mathrm{H}_2\mathrm{O}$  reaction calculated with different treatments of the rotation of the absorbed  $\mathrm{H}_2\mathrm{O}$

Figure 8 presents an Arrhenius plot of the rate constants for the (SiH₃O)₃Si−O−TiI₃* + H₂O reaction, calculated under different treatments of the rotational motion of the adsorbed H₂O molecule. Multiple curves compare how ignoring rotation, treating rotation as restricted, or allowing free rotation affects the temperature dependence of the rate constant. The plot highlights that including rotational degrees of freedom lowers the rate constants and slightly modifies the Arrhenius activation energy, reflecting the impact of rotational entropy on the reaction kinetics.

|T (K)|k_TST (s⁻¹)|k_SC-TST (s⁻¹)|
|-----:|-----------:|--------------:|
|423.15|1.43 × 10⁰|1.45 × 10⁰|
|473.15|1.56 × 10¹|1.57 × 10¹|
|523.15|1.08 × 10²|1.08 × 10²|
|573.15|5.82 × 10²|5.84 × 10²|
|623.15|2.04 × 10³|2.04 × 10³|
|673.15|6.92 × 10³|6.94 × 10³|
|723.15|1.72 × 10⁴|1.73 × 10⁴|

Answer: Yes, including rotational motion decreases the rate constant compared to ignoring rotation.

Answer: The restricted rotation model produces a slightly lower activation energy (4.8 kcal/mol) compared to ignoring rotation (5.1 kcal/mol).

Answer: The treatment of H₂O rotation directly affects the free energy of the adsorbed complex, which in turn changes the activation barrier and the magnitude of the rate constant. Ignoring rotation overestimates the rate constant by underestimating the free energy barrier, while including full rotational freedom can underestimate it due to overestimation of rotational entropy. This highlights the importance of accurately modeling molecular rotations when predicting surface reaction kinetics in ALD processes, as small differences can significantly impact predicted reaction rates and process design.

Answer: No rotation (rotation ignored, qrot = 1), Restricted rotation (partial rotational freedom), Free rotation (V₀ = 0, σ = 1)


Fig. 3. Coverage of the substrate surface during the first 10 ALD cycles. Simulations with and without densification mechanisms are compared to experimental results. The starting surface used was a chemical  $\mathrm{SiO_2}$  oxide surface prepared with DDC3 method of SMS machine (representing an experimental OH surface density of  $50\%$ ). The ALD reactor used was PulsarTM 2000.

The line chart illustrates the surface coverage % over number of ALD cycles,  comparing experiment  with two KMC simulations (with and without densification). Coverage increases steadily with more cycles for all cases, 'With Densification' achievies the coverage closest to experiment.

| ALD Cycle | Experimental | Without Densification | With Densification |
|------------|--------------|----------------------|--------------------|
| 0          | 0            | 0                  | 0                |
| 1          | 39           | 39                 | 39                 |
| 2          | 44           | 40                   | 49                 |
| 3          | 53           | 41                   | 62                 |
| 4          | 63           | 42                   | 69                 |
| 5          | 71           | 43                   | 77                 |
| 6          | 74           | 43                   | 81                 |
| 7          | 78           | 44                   | 86                 |
| 8          | 84           | 45                   | 89                 |
| 9          | 94           | 47                   | 92                 |
| 10         | 100          | 47                   | 94                |

Answer: Experimental, With densification, Without densification

Answer: The plot shows that including densification prevents early stalling and allows coverage to keep increasing with cycle number. Without densification, the simulated coverage quickly plateaus around ~40–50%. The “with densification” curve continues rising and closely follows the experimental trend toward near-complete coverage by 10 cycles. This indicates densification is necessary in the model to reproduce the experiment more closely.

Answer: It generally underestimates the coverage compared to the experimental data.

Answer: 47 %


Fig. 6. Comparison of numerically calculated growth rate with experimental data of Chen et al. [28].

This plot represents the reactor-scale model by comparing predicted GaN growth rates with experimental data from Chen et al. over 700–1300 K. The model correctly reproduces the shift from kinetic control at low temperatures to a diffusion-limited plateau near 900 K and the decline at very high temperatures. The close agreement demonstrates that the mechanism reliably captures GaN growth behavior across key temperature regimes. Graph has inverse temperature (1000/T).

| 1000/T (1/K) | Growth Rate (µm/hr) | Work               |
|-------------|---------------------|--------------------|
| 0.73         | 1.45                | This work          |
| 0.75         | 1.80                | Experimental study |
| 0.77         | 1.90                | Experimental study |
| 0.80         | 2.00                | Experimental study |
| 0.83         | 2.10                | This work          |
| 0.87         | 2.05                | This work          |
| 0.92         | 2.00                | This work          |
| 0.97         | 1.95                | This work          |
| 1.02         | 1.90                | Experimental study |
| 1.10         | 1.70                | Experimental study |
| 1.27         | 0.50                | Experimental study |
| 1.30         | 0.25                | This work          |
| 1.32         | 0.05                | Experimental study |

Answer:
1. Desorption/Thermodynamic limitation (High T).

, 2. Mass Transport (Diffusion) limitation (Mid T).

, 3. Surface Kinetic limitation (Low T).

Answer: The comprehensive multi-regime model is computationally expensive and impractical for real-time control. The risk of using the simple Arrhenius model is severe error if the process operates outside its fitted kinetic zone. It would fail to predict the growth rate plateau (leading to overestimation) and the high-T decline (leading to unsafe temperature choices), potentially causing poor film quality and reactor problems.

Answer:
Low-T (High 1000/T): Kinetic control – Growth rate increases sharply with temperature; limited by the thermal activation of surface chemical reactions.

Mid-T (Plateau): Diffusion control – Rate is constant; limited by the transport of reactants through the boundary layer to the surface.

High-T (Low 1000/T): Declining regime – Rate decreases; limited by premature gas-phase reactions or depletion of reactants before they reach the surface, or thermodynamic reversal.

Answer: Yes.The model's proven accuracy across regimes allows it to identify the diffusion-limited plateau (near 900 K) as the optimal window. In this regime, the growth rate is high and, most importantly, insensitive to minor temperature fluctuations, which is the key to achieving excellent thickness uniformity across a production wafer. The model reliably defines this window, avoiding the inefficient kinetic and problematic high-T regimes.


Fig. 4. Comparison of relative intermixing ratios for position B (water side) and C (TMA side) with different gap sizes, and the relative intermixing ratios is defined as the concentration ratio of the foreign gas to the home gas.

The line chart shows the relationship between gap size and relative intermixing ratio at two positions, B and C

| Gap size (mm) | Position B (Ratio) | Position C (Ratio) |
|---|---|---|
| 1.0 | 0.005 | 0.250 |
| 1.5 | 0.001 | 0.060 |
| 2.0 | 0.000 | 0.030 |

Answer: Position C (TMA side) experiences higher intermixing because water has a higher inlet vapor pressure than TMA, resulting in stronger diffusive transport of water molecules toward the TMA zone. At 1 mm gap, the relative intermixing ratio at position C is approximately 0.25 (1:4 water to TMA), while position B shows only about 0.01. This asymmetry reflects the different volatilities of the two precursors.

Answer: It is defined as the concentration ratio of the foreign gas to the home gas at each monitoring position.

Answer: The relative intermixing ratio decreases dramatically from approximately 0.25 to 0.03, representing roughly an 8-fold reduction.

Answer: No. At 2 mm gap size, both positions show low intermixing ratios (below 0.03), indicating effective precursor separation with minimal risk of unwanted CVD-type reactions.


Fig. 6. The effects of wafer temperature  $150^{\circ} \mathrm{C}$ ,  $200^{\circ} \mathrm{C}$  and  $250^{\circ} \mathrm{C}$  on the precursor intermixing with gap size and pumping pressure fixed at  $1.5 \mathrm{~mm}$  and 0.22 torr: (a) TMA and water concentration in  $\mathrm{mol} / \mathrm{m}^3$  at position B (water side), and (b) at position C (TMA side). The simulation time is  $0.04 \mathrm{~s}$  with  $1.5 \mathrm{~mm}$  gap size. Fig. 9. Growth per cycle of bulk  $\mathrm{Al}_2\mathrm{O}_3$  thin films with different relative pumping pressure (to the base pressure, 0.22 torr) 0, 0.05 and 0.1 torr with  $1.5 \mathrm{~mm}$  gap size and  $200^{\circ} \mathrm{C}$  wafer temperature.

Growth per cycle (GPC) of Al₂O₃ thin films as a function of dosing time for three relative pumping pressures (0, 0.05, and 0.1 torr above the base pressure of 0.22 torr) at 1.5 mm gap size and 200°C wafer temperature. All three curves show nearly identical behavior, with rapid growth during the unsaturated period (0 to 0.015 s) followed by saturation at approximately 1.2 Å/cycle.

| Time (s) | Al₂O₃-0 torr (Å/cycle) | Al₂O₃-0.05 torr (Å/cycle) | Al₂O₃-0.1 torr (Å/cycle) |
|---|---|---|---|
| 0.000 | 0.00 | 0.00 | 0.00 |
| 0.002 | 0.20 | 0.18 | 0.15 |
| 0.005 | 0.68 | 0.62 | 0.58 |
| 0.008 | 0.95 | 0.90 | 0.85 |
| 0.010 | 1.12 | 1.08 | 1.02 |
| 0.012 | 1.18 | 1.16 | 1.14 |
| 0.015 | 1.21 | 1.21 | 1.20 |
| 0.020 | 1.23 | 1.23 | 1.23 |
| 0.030 | 1.23 | 1.23 | 1.23 |
| 0.040 | 1.23 | 1.23 | 1.23 |

Answer: The saturated GPC remains essentially constant at approximately 1.2 Å/cycle regardless of pumping pressure, indicating that pumping pressure has very weak influence on the chemical deposition process.

Answer: The ALD process is self-limiting, meaning deposition stops once all reactive surface sites are consumed. While different pumping pressures affect precursor intermixing levels, the dominant precursor concentrations at the wafer surface remain comparable across all conditions. Since surface reaction kinetics depend primarily on temperature and precursor availability at saturating conditions, the final GPC is determined by the surface site density rather than pumping efficiency.

Answer: Approximately 0.015 s, after which the growth per cycle plateaus.

Answer: It represents the thickness of Al₂O₃ film deposited during one complete ALD cycle, measured in angstroms.


Fig. 7. Growth per cycle of bulk  $\mathrm{Al}_2\mathrm{O}_3$  thin films with different deposition temperatures,  $150^{\circ} \mathrm{C}$ ,  $200^{\circ} \mathrm{C}$  and  $250^{\circ} \mathrm{C}$  with  $1.5 \mathrm{~mm}$  gap size and the ideal pumping condition (0.22 torr).

Growth per cycle (GPC) of Al₂O₃ thin films as a function of dosing time at three deposition temperatures (150°C, 200°C, 250°C) with 1.5 mm gap size and 0.22 torr pumping pressure. Higher temperatures yield higher saturated GPC values, with 250°C reaching approximately 1.23 Å/cycle and 150°C reaching approximately 1.18 Å/cycle. All curves saturate around 0.015 s.

| Time (s) | Al₂O₃-250°C (Å/cycle) | Al₂O₃-200°C (Å/cycle) | Al₂O₃-150°C (Å/cycle) |
|---|---|---|---|
| 0.000 | 0.00 | 0.00 | 0.00 |
| 0.002 | 0.35 | 0.30 | 0.25 |
| 0.005 | 0.80 | 0.75 | 0.70 |
| 0.008 | 1.10 | 1.05 | 1.00 |
| 0.010 | 1.19 | 1.16 | 1.12 |
| 0.012 | 1.22 | 1.19 | 1.16 |
| 0.015 | 1.24 | 1.21 | 1.18 |
| 0.020 | 1.25 | 1.22 | 1.20 |
| 0.030 | 1.25 | 1.22 | 1.20 |
| 0.040 | 1.25 | 1.22 | 1.20 |

Answer: Temperature has a noticeably stronger effect on saturated GPC than pumping pressure. While all pumping pressure curves in Figure 9 converge to essentially the same value, the temperature curves show clear separation at saturation, with 250°C achieving approximately 0.05 Å/cycle higher GPC than 150°C. This reflects the temperature dependence of surface reaction kinetics described by the Arrhenius equation, where higher temperatures increase reaction rates and surface reactivity.

Answer: Higher temperature increases the reactivity of surface species and molecular kinetic energy, leading to higher collision probabilities and faster reaction rates, which ultimately produces a higher saturated film thickness per cycle.

Answer: No. The three curves are nearly overlapping during the early unsaturated growth period, with differences becoming apparent only as saturation is approached.

Answer: Approximately 4 nm/s, calculated from the saturated GPC of about 1.2 Å/cycle divided by a total cycle time of 0.03 s (two half-reactions of 0.015 s each).


Fig. 8. Growth per cycle of bulk  $\mathrm{Al}_2\mathrm{O}_3$  thin films with different gap sizes 1, 1.5 and  $2 \mathrm{~mm}$  with ideal pumping condition (0.22 torr) and  $200^{\circ} \mathrm{C}$  wafer temperature.

Growth per cycle (GPC) of Al₂O₃ thin films as a function of dosing time for three gap sizes (1, 1.5, and 2 mm) at 200°C and 0.22 torr pumping pressure. Larger gaps reach saturation faster (2 mm saturates at approximately 0.01 s) while smaller gaps require longer dosing times (1 mm saturates at approximately 0.025 s). The 1 mm and 1.5 mm gaps achieve slightly higher saturated GPC than 2 mm.

| Time (s) | Al₂O₃-1mm (Å/cycle) | Al₂O₃-1.5mm (Å/cycle) | Al₂O₃-2mm (Å/cycle) |
|---|---|---|---|
| 0.000 | 0.00 | 0.00 | 0.00 |
| 0.002 | 0.02 | 0.15 | 0.35 |
| 0.004 | 0.18 | 0.50 | 0.75 |
| 0.006 | 0.38 | 0.82 | 1.00 |
| 0.008 | 0.60 | 1.02 | 1.12 |
| 0.010 | 0.78 | 1.15 | 1.17 |
| 0.012 | 0.92 | 1.19 | 1.19 |
| 0.015 | 1.08 | 1.22 | 1.20 |
| 0.020 | 1.19 | 1.23 | 1.20 |
| 0.025 | 1.22 | 1.23 | 1.20 |
| 0.030 | 1.23 | 1.23 | 1.20 |
| 0.040 | 1.23 | 1.23 | 1.20 |

Answer: Smaller gap sizes significantly increase the critical dosing time. The 1 mm gap requires approximately 0.025 s to reach saturation, while 1.5 mm needs about 0.012 s and 2 mm only 0.01 s. This occurs because smaller gaps hinder gas flow and reduce convective mass transport, making diffusion the dominant transport mechanism. Since diffusion is slower than convection, precursor delivery to the surface takes longer with narrower gaps.

Answer: The narrow 1 mm gap restricts gas flow, causing mass transport to be dominated by slower diffusive processes rather than faster convective transport, which delays precursor delivery to the wafer surface.

Answer: The 1 mm gap achieves the highest saturated GPC (approximately 1.23 Å/cycle), slightly higher than 1.5 mm and 2 mm gaps.

Answer: The 1.5 mm gap offers the best compromise, achieving a saturated GPC comparable to 1 mm while requiring a much shorter critical dosing time (0.012 s versus 0.025 s), and also showing less precursor intermixing than 1 mm.


FIG. 3. (Color online)  $\mathrm{Al}_2\mathrm{O}_3$  film growth rate in  $\mathring{\mathrm{A}}/$  cycle for: (a) 8 s purging experiments; (b)  $20\mathrm{s}$  purging experiments. Sample A is located in the inlet area and sample C in the outlet area.

Al₂O₃ growth per cycle (GPC) versus temperature for five wafer positions with 8 s purging time. GPC increases from 100°C to 200°C then decreases at 250°C, demonstrating the ALD temperature window. Sample A (inlet) shows highest GPC (~1.18 Å/cycle at 200°C) while sample C (outlet) shows lowest values throughout.

Same measurement with 20 s purging time. The longer purge slightly increases peak GPC for most samples. Notably, the turning temperature shifts from 200°C to 150°C for samples D and E, indicating earlier surface saturation due to extended precursor contact time.

| Temperature (°C) | A | B | C | D | E |
|---|---|---|---|---|---|
| 100 | 1.05 | 1.02 | 0.98 | 1.00 | 1.00 |
| 150 | 1.10 | 1.07 | 1.00 | 1.05 | 1.05 |
| 200 | 1.15 | 1.12 | 1.10 | 1.15 | 1.15 |
| 250 | 1.10 | 1.08 | 0.95 | 1.10 | 1.05 |

| Temperature (°C) | A | B | C | D | E |
|---|---|---|---|---|---|
| 100 | 1.10 | 1.05 | 0.98 | 1.00 | 1.00 |
| 150 | 1.15 | 1.10 | 1.00 | 1.05 | 1.05 |
| 200 | 1.20 | 1.15 | 1.10 | 1.15 | 1.15 |
| 250 | 1.10 | 1.08 | 0.95 | 1.10 | 1.05 |

Answer: Sample A (inlet position) consistently shows the highest GPC across all temperatures. This occurs because precursor concentration remains higher for longer at the inlet, increasing collision probability with reactive surface sites. At the outlet (sample C), precursors are diluted by byproduct CH₄ and partially consumed by reactions upstream.

Answer: The five wafer sample positions inside the chamber: A at inlet, C at outlet, B and D at upper and lower positions, and E at center.

Answer: Enhanced desorption of formed surface species at higher temperatures reduces net film deposition.

Answer: (1) Peak GPC slightly increases for most samples due to longer precursor contact time, (2) the turning temperature shifts to 150°C for samples D and E as surface saturation is reached earlier, and (3) outlet sample C remains at similar GPC since it was already saturated in 8 s purging.


FIG. 4. (Color online) Comparisons of surface-averaged  $\mathrm{Al}_2\mathrm{O}_3$  film growth rates in  $\mathring{\mathrm{A}}/$  cycle by experimental and numerical investigations.

The line chart illustrates the growth per cycle at different temperatures for two experimental conditions and one numerical simulation

| Temperature (°C) | Experimental-8s purging (Å/Cycle) | Experimental-20s purging (Å/Cycle) | Numerical simulation (Å/Cycle) |
|---|---|---|---|
| 100 | 1.01 | 1.04 | 1.09 |
| 150 | 1.06 | 1.14 | 1.19 |
| 200 | 1.14 | 1.16 | 1.23 |
| 250 | 1.10 | 1.07 | 1.21 |

Answer: The numerical GPC closely follows the experimental trends, with values approximately 0.05 Å/cycle higher on average. This slight overestimation is attributed to model simplifications such as assuming 100% hydroxyl coverage at the initial state and neglecting intermediate reaction products. The overall agreement validates the numerical model for studying ALD process details.

Answer: Black squares: experimental data with 8 s purging; red circles: experimental data with 20 s purging; green triangles: numerical simulation results.

Answer: 200°C, with approximately 1.22 Å/cycle.

Answer: (1) The model assumes perfect 100% hydroxyl coverage on wafer surfaces initially, (2) complex intermediate products from DFT studies are neglected for computational feasibility, and (3) local variations in precursor concentration and surface conditions are simplified.


FIG. 8. (Color online) Surface deposition rate of bulk  $\mathrm{Al}_2\mathrm{O}_3\langle \mathrm{s}\rangle$  at five different positions in TMA pulsing step for 100, 150, 200, and  $250^{\circ}\mathrm{C}$ , respectively. The bulk  $\mathrm{Al}_2\mathrm{O}_3$  growth rate is obtained from summation of the resulted bulk species  $\mathrm{O}\langle \mathrm{s}\rangle$  and  $\mathrm{Al}\langle \mathrm{s}\rangle$  in the two half reactions described in Eq. (17). Point A is located in the inlet area and point C in the outlet area.

Bulk Al₂O₃ deposition rate at five chamber positions during TMA pulse at 100°C. Inlet sample A shows the fastest and highest response (~1.6×10⁻⁴ kg/m²s), peaking around 3 ms. Other positions (B, C, D, E) show delayed and lower peak rates.

Same at 150°C. Sample A responds similarly; other samples show slightly earlier peaks compared to 100°C.

Same at 200°C. Peak rates and timing patterns remain consistent with lower temperatures.

Same at 250°C. Overall behavior is similar, confirming that positional differences in deposition rate are determined primarily by precursor transport rather than temperature.

| Flow Time (ms) | A ( kg/m^2s ) | B ( kg/m^2s ) | C ( kg/m^2s ) | D ( kg/m^2s ) | E ( kg/m^2s ) |
|---|---|---|---|---|---|
| 1.5 | 0.80e-4 | 0.00 | 0.00 | 0.00 | 0.10e-4 |
| 2.0 | 1.65e-4 | 0.00 | 0.00 | 0.00 | 0.40e-4 |
| 2.5 | 1.20e-4 | 0.00 | 0.00 | 0.00 | 0.70e-4 |
| 3.0 | 0.40e-4 | 0.00 | 0.00 | 0.00 | 0.95e-4 |
| 3.5 | 0.10e-4 | 0.00 | 0.00 | 0.00 | 1.00e-4 |
| 4.0 | 0.00 | 0.00 | 0.05e-4 | 0.00 | 0.80e-4 |
| 5.0 | 0.00 | 0.05e-4 | 0.30e-4 | 0.05e-4 | 0.50e-4 |
| 6.0 | 0.00 | 0.20e-4 | 0.60e-4 | 0.20e-4 | 0.20e-4 |
| 7.0 | 0.00 | 0.50e-4 | 0.80e-4 | 0.50e-4 | 0.05e-4 |
| 8.0 | 0.00 | 0.75e-4 | 0.70e-4 | 0.75e-4 | 0.00 |
| 9.0 | 0.00 | 0.75e-4 | 0.40e-4 | 0.75e-4 | 0.00 |
| 10.0 | 0.00 | 0.50e-4 | 0.15e-4 | 0.50e-4 | 0.00 |
| 12.0 | 0.00 | 0.10e-4 | 0.00 | 0.10e-4 | 0.00 |

| Flow Time (ms) | A ( kg/m^2s ) | B ( kg/m^2s ) | C ( kg/m^2s ) | D ( kg/m^2s ) | E ( kg/m^2s ) |
|---|---|---|---|---|---|
| 2.0 | 1.68e-4 | 0.00 | 0.00 | 0.00 | 0.60e-4 |
| 3.0 | 0.10e-4 | 0.00 | 0.00 | 0.00 | 1.05e-4 |
| 4.0 | 0.00 | 0.00 | 0.05e-4 | 0.00 | 0.50e-4 |
| 5.0 | 0.00 | 0.05e-4 | 0.35e-4 | 0.05e-4 | 0.10e-4 |
| 6.0 | 0.00 | 0.30e-4 | 0.70e-4 | 0.30e-4 | 0.00 |
| 7.0 | 0.00 | 0.60e-4 | 0.90e-4 | 0.60e-4 | 0.00 |
| 8.0 | 0.00 | 0.85e-4 | 0.60e-4 | 0.85e-4 | 0.00 |
| 9.0 | 0.00 | 0.70e-4 | 0.20e-4 | 0.70e-4 | 0.00 |
| 10.0 | 0.00 | 0.40e-4 | 0.00 | 0.40e-4 | 0.00 |

| Flow Time (ms) | A ( kg/m^2s ) | B ( kg/m^2s ) | C ( kg/m^2s ) | D ( kg/m^2s ) | E ( kg/m^2s ) |
|---|---|---|---|---|---|
| 2.0 | 1.70e-4 | 0.00 | 0.00 | 0.00 | 0.80e-4 |
| 3.0 | 0.05e-4 | 0.00 | 0.00 | 0.00 | 1.25e-4 |
| 4.0 | 0.00 | 0.00 | 0.05e-4 | 0.00 | 0.40e-4 |
| 5.0 | 0.00 | 0.05e-4 | 0.35e-4 | 0.05e-4 | 0.05e-4 |
| 6.0 | 0.00 | 0.35e-4 | 0.75e-4 | 0.35e-4 | 0.00 |
| 7.0 | 0.00 | 0.70e-4 | 0.90e-4 | 0.70e-4 | 0.00 |
| 8.0 | 0.00 | 0.90e-4 | 0.50e-4 | 0.90e-4 | 0.00 |
| 9.0 | 0.00 | 0.60e-4 | 0.10e-4 | 0.60e-4 | 0.00 |
| 10.0 | 0.00 | 0.30e-4 | 0.00 | 0.30e-4 | 0.00 |

| Flow Time (ms) | A ( kg/m^2s ) | B ( kg/m^2s ) | C ( kg/m^2s ) | D ( kg/m^2s ) | E ( kg/m^2s ) |
|---|---|---|---|---|---|
| 2.0 | 1.72e-4 | 0.00 | 0.00 | 0.00 | 0.90e-4 |
| 2.5 | 0.40e-4 | 0.00 | 0.00 | 0.00 | 1.25e-4 |
| 3.0 | 0.05e-4 | 0.00 | 0.00 | 0.00 | 0.90e-4 |
| 4.0 | 0.00 | 0.00 | 0.05e-4 | 0.00 | 0.20e-4 |
| 5.0 | 0.00 | 0.10e-4 | 0.30e-4 | 0.10e-4 | 0.00 |
| 6.0 | 0.00 | 0.40e-4 | 0.80e-4 | 0.40e-4 | 0.00 |
| 7.0 | 0.00 | 0.80e-4 | 0.85e-4 | 0.80e-4 | 0.00 |
| 8.0 | 0.00 | 0.92e-4 | 0.40e-4 | 0.92e-4 | 0.00 |
| 9.0 | 0.00 | 0.50e-4 | 0.10e-4 | 0.50e-4 | 0.00 |

Answer: Sample A (inlet) consistently shows the highest and fastest deposition rate across all temperatures. This correlates with flow simulation results showing that A experiences higher precursor concentrations for longer periods. The sample closest to precursor inlets reacts first and most intensely before precursors diffuse to other regions.

Answer: Approximately 1.6–1.8×10⁻⁴ kg/m²s across all temperatures.

Answer: By summing the deposition rates of bulk species O⟨s⟩ and Al⟨s⟩ from the two half reactions (TMA and water pulses).

Answer: No. The relative ordering (A highest, then E, then B/D, then C lowest) remains consistent across all four temperatures, indicating that flow and precursor distribution dominate over temperature effects for spatial variations.


Fig. 6 Comparison of the dissociation of  $\mathrm{Cu(acac)}_2$  into  $\mathrm{Cu(acac)}$  and acac on  $\mathrm{Cu(110)}$ ,  $\mathrm{Cu}_2\mathrm{O(111)}$ , and  $\mathrm{CuO(111)}$  surfaces at  $600\mathrm{K}$ .

The line chart shows the decrease in the number of Cu(acac)_2 over time for three different surfaces: Cu(110), Cu_2O(111), and CuO(111).

| Time (ps) | Cu(110) | Cu₂O(111) | CuO(111) |
|---|---|---|---|
| 0.0 | 24 | 24 | 24 |
| 5.0 | 24 | 24 | 24 |
| 10.0 | 24 | 22 | 24 |
| 12.5 | 21 | 20 | 23 |
| 15.0 | 17 | 18 | 22 |
| 17.5 | 17 | 18 | 22 |
| 20.0 | 16 | 16 | 21 |
| 22.5 | 13 | 12 | 19 |
| 25.0 | 9 | 12 | 19 |
| 27.5 | 5 | 12 | 18 |
| 30.0 | 5 | 9 | 17 |
| 32.5 | 4 | 9 | 16 |
| 35.0 | 4 | 4 | 13 |
| 37.5 | 2 | 3 | 11 |
| 40.0 | 2 | 3 | 7 |
| 42.5 | 2 | 2 | 4 |
| 45.0 | 1 | 2 | 3 |
| 47.5 | 1 | 1 | 3 |
| 50.0 | 0 | 0 | 2 |
| 52.5 | 0 | 0 | 2 |
| 55.0 | 0 | 0 | 1 |
| 60.0 | 0 | 0 | 1 |
| 70.0 | 0 | 0 | 1 |
| 72.5 | 0 | 0 | 0 |
| 80.0 | 0 | 0 | 0 |

Answer:
Black squares represent Cu(110).

, Red circles represent Cu2O(111).

, Blue triangles represent CuO(111).

Answer: CuO(111) is slowest, because its curve drops later and reaches zero at a later time than the other two.

Answer: About 70 ps.

Answer: The paper concludes that copper rich surfaces react faster than CuO(111) in decomposing Cu(acac)2. This trend suggests that surface Cu atoms are the more reactive sites toward the acac ligand. In an ALD context, this implies that the substrate oxidation state can strongly influence precursor dissociation kinetics

icdar2026-competition-data/test/gold_standard_test_set/atomic-layer-deposition/simulation-usecase/41/Xiao Hu et al.pdf


Fig. 8 Product evolution for the surface reactions between  $\mathrm{Cu(acac)}_2$  and atomic H (a and b), water (c and d), and ozone (e and f), respectively.

Gas phase product evolution versus time for the surface reaction between Cu(acac)2 and atomic H.

Surface elemental inventory (C, H, O) versus time during the surface reaction between Cu(acac)2 and atomic H.

Gas phase product evolution versus time for the surface reaction between Cu(acac)2 and H2O.

Surface elemental inventory (C, H, O) versus time during the surface reaction between Cu(acac)2 and H2O.

Gas phase product evolution versus time for the surface reaction between Cu(acac)2 and ozone, showing COx and HxOy as major byproducts.

Surface elemental inventory (C, H, O) versus time during the surface reaction between Cu(acac)2 and ozone, showing strong surface oxidation and carbon loss.

| Time (ps) | H (×0.05) | CxHy | H₂O | H₂ (×0.05) | Others |
|---|---|---|---|---|---|
| 0 | 100 | 0 | 0 | 0 | 0 |
| 20 | 80 | 10 | 35 | 10 | 15 |
| 40 | 45 | 40 | 60 | 22 | 10 |
| 60 | 20 | 65 | 68 | 32 | 5 |
| 80 | 5 | 85 | 68 | 37 | 2 |
| 100 | 0 | 90 | 65 | 39 | 1 |
| 150 | 0 | 91 | 55 | 39 | 0 |
| 200 | 0 | 93 | 50 | 39 | 0 |

| Time (ps) | C (Number) | H (Number) | O (Number) |
|---|---|---|---|
| 0 | 240 | 350 | 100 |
| 25 | 180 | 300 | 60 |
| 50 | 40 | 100 | 30 |
| 75 | 10 | 50 | 20 |
| 100 | 10 | 50 | 35 |
| 150 | 10 | 70 | 40 |
| 200 | 10 | 70 | 45 |

| Time (ps) | H₂O (×0.01) | H(acac) | acac (approx) | H₂(acac) |
|---|---|---|---|---|
| 0 | 20.0 | 0 | 0 | 0 |
| 100 | 19.8 | 6 | 1 | 0 |
| 200 | 19.5 | 8 | 1 | 0 |
| 400 | 19.0 | 14 | 2 | 0 |
| 600 | 18.8 | 14 | 2 | 2 |
| 800 | 18.5 | 15 | 2 | 2 |

| Time (ps) | H (Number) | O (Number) | C (Number) |
|---|---|---|---|
| 0 | 350 | 150 | 240 |
| 100 | 500 | 190 | 210 |
| 200 | 530 | 210 | 200 |
| 400 | 530 | 230 | 170 |
| 600 | 530 | 240 | 150 |
| 800 | 540 | 240 | 150 |

| Time (ps) | O₃ (×0.1) | O | O₂ (×0.1) | CO+CO₂ | OH+H₂O+HO₂ | Others |
|---|---|---|---|---|---|---|
| 0 | 100 | 0 | 0 | 0 | 0 | 0 |
| 50 | 60 | 60 | 50 | 10 | 60 | 25 |
| 100 | 20 | 120 | 85 | 40 | 90 | 30 |
| 150 | 5 | 130 | 98 | 55 | 90 | 30 |
| 200 | 0 | 100 | 102 | 70 | 80 | 25 |
| 300 | 0 | 50 | 108 | 90 | 55 | 22 |
| 450 | 0 | 15 | 110 | 100 | 35 | 22 |
| 600 | 0 | 0 | 110 | 110 | 20 | 22 |

| Time (ps) | O (Number) | H (Number) | C (Number) |
|---|---|---|---|
| 0 | 100 | 330 | 240 |
| 50 | 300 | 220 | 180 |
| 150 | 480 | 200 | 130 |
| 300 | 550 | 240 | 100 |
| 450 | 580 | 270 | 80 |
| 600 | 600 | 290 | 70 |

Answer:
Reactivity order is atomic H, then ozone, then H2O.

Atomic H shows rapid formation of hydrogen containing products and fast changes in surface composition in (a,b).

Ozone shows substantial formation of HxOy and COx products in (e) and strong surface oxygen buildup in (f).

Water shows slower product formation and more gradual surface evolution in (c,d).

Answer: The paper reports that HxOy evolution starts about 10 ps earlier than COx evolution.  This implies that ozone reacts first with hydrogen in the Cu(acac)2 derived ligands before extensive carbon oxidation occurs. That sequencing is consistent with an initial hydrogen abstraction step followed by deeper oxidation to CO and CO2.

Answer: They argue that if HxOy re adsorb, then protons become available on the surface.  Those protons can participate in ligand exchange during the next Cu(acac)2 pulse, similar to the water based ligand exchange mechanism. In practice, this links ozone exposure to creation of reactive, protonated surface species that can help sustain self limiting cycling.

Answer: “Gas phase” panels plot counts of gaseous products, while “Surface” panels plot how many C, H, and O atoms remain associated with the surface region during the simulation.


Figure 4. ALD of  $\mathrm{SiO_2}$  and  $\mathrm{Si}_3\mathrm{N}_4$ . Energetics for the Bound Reactants (BR), Transition State (TS), Bound Products (BP) and Unbound Products (UP) relative to the Unbound Reactants (UR) (described in Figure 3) for the reaction of  $\mathrm{SiH}_2(\mathrm{NH}_2)_2$  (triangles, dashed lines),  $\mathrm{SiH}_2(\mathrm{N}(\mathrm{CH}_3)_2)_2$  (squares, solid lines) with the cluster models of an aminated nitride surface (red) and a hydroxylated oxide surface (green).  $\Delta E$  values are given in  $\mathrm{kJ} \mathrm{mol}^{-1}$  and were determined from BP86/SV(P) DFT calculations. Activation energies  $E_{\mathrm{act}}$  are listed in the inset. Reproduced with permission.[69] Copyright 2014, American Chemical Society.

icdar2026-competition-data/test/gold_standard_test_set/atomic-layer-deposition/simulation-usecase/47/Simon D. Elliott et al.pdf


The figure shows two overlapping software screenshots displaying line plots of electrochemical measurements. The left panel appears to show a voltage profile (likely charge-discharge cycles over time), while the right panel displays a capacity (or similar cumulative metric) plotted against cycle number or time. Different colored curves in the right plot suggest comparison across multiple channels or cell conditions (e.g., different materials or electrolytes). The consistent curvature upward indicates increasing cumulative response over repeated measurements

| x | y1 | y2 | y3 |
|---|---|---|---|
| 0 | 0.178 | 0.178 | 0.178 |
| 1 | 0.256 | 0.256 | 0.256 |
| 2 | 0.334 | 0.334 | 0.334 |
| 3 | 0.412 | 0.412 | 0.412 |
| 4 | 0.490 | 0.490 | 0.490 |
| 5 | 0.568 | 0.568 | 0.568 |
| 6 | 0.646 | 0.646 | 0.646 |
| 7 | 0.724 | 0.724 | 0.724 |
| 8 | 0.802 | 0.802 | 0.802 |
| 9 | 0.880 | 0.880 | 0.880 |

Answer: The curvature in the right plot suggests that the system exhibits a non-linear increase in response over time or cycles. This is commonly seen in battery or capacitor systems, where the cumulative capacity or state of charge grows more slowly as the system approaches saturation or stabilises after initial activation. The separation between the curves may indicate differences in performance across different test conditions, such as varying materials, electrolytes, or cycle numbers. This type of data helps evaluate long-term stability and efficiency.

Answer: Three.

Answer: No

Answer: Charge - discharge efficiency, Cycle-to-cycle capacity retention

icdar2026-competition-data/test/gold_standard_test_set/atomic-layer-etching/experimental-usecase/1/Atomic Layer Etching An Industry Perspective.pdf


FIG. 4. Comparison of literature values of the etch per cycle (EPC) for thermal HF/TMA processes and the  $\mathrm{SF_6}$  plasma/TMA process outlined here.10,14,15,18 Temperatures reported from this work are measured using in situ spectroscopic ellipsometry, while the literature values are the reported set point temperatures. Substrate temperature values from the literature may deviate depending on process conditions and reactors used, as discussed in more detail in the supplementary material. Additional data for thermal ALE processes utilizing alternate reactants are presented in Fig. S3 in the supplementary material.

Etch per cycle increases with substrate temperature for all reported thermal ALE chemistries, with the SF₆ plasma/TMA process showing the strongest activation. This work reaches ~1.8 Å/cycle at 200 °C and increases to ~3.5 Å/cycle at 300 °C, exceeding all HF/TMA literature values. The highest reported HF/TMA result (Cano et al.) reaches ~2.5 Å/cycle at 300 °C, while other studies remain at or below ~1 Å/cycle. The comparison highlights a clear performance advantage of plasma-assisted fluorination.

| Substrate Temperature (°C) | This work (SF₆/TMA) | Canon HF/TMA | Cheng HF/TMA | Lee HF/TMA | Zyvox HF/TMA |
|---|---|---|---|---|---|
| 150 | ~0.2 | ~0.0 | ~0.0 | ~0.0 | ~0.0 |
| 200 | ~1.2 | ~0.6 | ~0.4 | ~0.3 | ~0.2 |
| 250 | ~2.7 | ~1.5 | ~0.9 | ~0.7 | ~0.6 |
| 300 | ~3.5 | ~2.2 | ~1.3 | ~1.1 | ~1.0 |

Answer: Thermal HF/TMA process and SF6 plasma/TMA process.

Answer: The current work with SF6/TMA.

Answer: Approximately 275 °C.

Answer: The etch per cycle increases as the substrate temperature gets higher.

Answer: For increasing temperature, regardless of the chemistry, the EPC increases.

Answer: It could be that different types of AlOx are etched. It is known that deposition method of the substrate can have an impact on etch rate.

Answer: Zywotko has shown that there is deposition of 0.5 angstrom/cycle at 250 degrees celcius.

Answer: at 250 degrees celcius an etch rate of 3 angstrom/cycle is achieved.

Answer: The SF₆ plasma/TMA process shows much stronger temperature activation than HF/TMA chemistries. At 250 °C it already matches or exceeds the highest HF/TMA values reported at 300 °C, and at 300 °C it reaches ~3.5 Å/cycle. This indicates that plasma-assisted fluorination produces a more reactive surface for ligand exchange with TMA.

Answer: SF₆ plasma/TMA (this work), at ~3.5 Å/cycle.

Answer: SF₆ plasma produces a higher density of reactive fluorinated sites than HF gas exposure. The presence of energetic fluorine species increases fluorine coverage and accessibility at the surface, which enhances the efficiency of TMA-driven ligand exchange. This results in greater material removal per cycle at elevated temperature.

Answer: Yes

Answer: The SF₆ plasma ALE process (green squares) exhibits a significantly higher EPC compared to all the thermal HF/TMA processes (dashed lines) across the measured temperature range. For example, at 250 °C, the plasma process achieves an EPC of nearly 3.0 Å/cycle, whereas the thermal processes range from approximately 0.1 to 2.3 Å/cycle. Additionally, the plasma process maintains viable etch rates at lower temperatures where some thermal processes are inactive or show negligible rates.

Answer: The etch rate acts as a strong function of the substrate temperature, increasing steeply as the temperature rises. The EPC grows from approximately 0.2 Å/cycle at 155 °C to 3.4 Å/cycle at 285 °C. The data point at 140 °C lies slightly below zero, indicating a transition from etching to deposition (ALD mode) at very low temperatures.

Answer: A key advantage is the ability to achieve significant etching at lower processing temperatures. The figure shows that the plasma process delivers an etch rate of 0.8 Å/cycle at 185 °C, a temperature where thermal kinetics typically limit the reaction rate for HF-based processes. This makes the plasma variant suitable for substrates that cannot withstand the higher thermal budgets required for efficient thermal ALE.

Answer: The transition occurs around 140 °C, as indicated by the data point at 140 °C showing a slightly negative value (net deposition) and the point at 155 °C showing a positive etch rate.

Answer:
SF₆ plasma / TMA: The chemistry utilized in "This work" (Green square trace).

Thermal HF / TMA: The standard chemistry cited from literature sources (Cano, Hennessy, Lee, Zywotko).

Answer: The SF₆/TMA process exhibits a significantly higher etch rate compared to the HF/TMA processes. While the HF/TMA data (excluding Cano) generally remains below 1.5 Å/cycle, the SF₆/TMA process rapidly climbs from ~2.0 Å/cycle to >3.0 Å/cycle in this temperature window.

Answer: It implies the etch rate is limited by a plasma-driven surface reaction with low activation energy, not by a thermally activated step like precursor decomposition or ligand desorption.

Answer: Modern memory chips contain temperature-sensitive materials (e.g., metals, organics) that cannot withstand the >275°C required for thermal HF/TMA etching. The SF₆ plasma/TMA process achieves the necessary etch rate at ~200°C, compatible with these thermal constraints. Furthermore, the wide temperature window (200-300°C) offers robust process control across a wafer, which is critical for the high-aspect-ratio structures in 3D memory.

Answer: Yes, depending on the reactor and process conditions used.

Answer:
In previous work, ALD of AlF3 was observed to proceed in the wide temperature range of 50–300 °C when using a short 10 ms TMA dose.This suggests
that not only the temperature but also exposure to the precursor determines whether deposition or etching occurs.

Answer:
In comparison to thermal ALE, the plasma ALE process exhibits a higher etch per cycle (EPC) over the entire temperature range investigated
here.

Answer: A significant etch rate of 0.8A˚ /cycle was already observed at a relatively low temperature of 185 °C, highlighting one of the benefits of using a plasma process. It is thought that the fluorine radicals provided by the plasma allow for higher etch rates as a thicker fluorinated surface region is formed as compared to when using HF.

Answer: 3.4 Å.

Answer: 140 °C.

Answer: The plasma ALE process shows a higher EPC at all temperatures.

Answer: The TMA exposure dose, which resulted in AlF3 ALD for exposure times of 10 ms.

Answer: The plot shows that SF₆ plasma/TMA  gives the highest EPC at a given substrate temperature compared with the HF/TMA studies. That means you can achieve the same total etch depth at a lower temperature than with HF/TMA. Based on this trend alone, SF₆ plasma/TMA is the better choice for temperature-sensitive substrates.

Answer: At approximately 150 °C (EPC crossing 0).

Answer: Plasma etching with SF6/TMA.

Answer: Cano (HF/TMA): 2.5 Å/cycle, Hennessy (HF/TMA): 1.2 Å/cycle, Lee (HF/TMA): 0.45 Å/cycle

Answer: EPC increases with substrate temperature for all reported processes. The SF₆ plasma/TMA process shows a steeper increase and higher EPC values compared to thermal HF/TMA processes reported in the literature, particularly above 200 °C

Answer: The SF₆ plasma/TMA process reported in this work.

Answer: Temperatures in this work are measured in situ, while literature values are reported set points that may vary with reactor design and process conditions.

Answer: Higher EPC, Stronger T-dependence, Better efficiency vs. thermal ALE

Answer: Yes. The plasma-assisted ALE process consistently shows higher EPC than reported thermal HF/TMA processes for the entire temperature range studied.

Answer: At low substrate temperatures (~140 °C), the EPC is negative, indicating a transition from etching to deposition, which reflects ALD-like behavior.

Answer: Achieves higher etch rates even at relatively low temperatures, Ensures isotropic etching suitable for high aspect ratio 3D trenches, Allows precise control of film removal per cycle through temperature and pulse adjustments

Answer: Increasing the substrate temperature increases the EPC. At low temperatures (~140 °C), the EPC is slightly negative, indicating deposition-like behavior typical of ALD. As the temperature rises, the EPC increases steadily, reaching ~3.4 Å/cycle at 285 °C, showing that higher substrate temperatures enhance etching efficiency in the plasma-assisted ALE process.

icdar2026-competition-data/test/gold_standard_test_set/atomic-layer-etching/experimental-usecase/12/Isotropic plasma atomic layer etching of Al2O3 using a fluorine containing plasma and Al(CH3)3.pdf


Figure 12. Ion signal intensities versus temperature during  $\mathrm{BCl}_3$  exposure on  $\mathrm{AlF}_3$  powder with a heating rate of  $3^{\circ}\mathrm{C / min}$ . (a) Boron ligand-exchange species  $(\mathrm{BCl}_2\mathrm{F}^+$ ,  $\mathrm{BClF}_2^+$  and  $\mathrm{BF}_3^+$ ) and  $\mathrm{BCl}_3^+$  reactant. (b)  $\mathrm{AlCl}_3^+$  and  $\mathrm{AlCl}_2^+$  etch products.

The line chart shows the intensity of various ions (BCl₃⁺, BCIF₂⁺, BCl₂F⁺, BF₃⁺) as a function of temperature. The intensity decreases for BCl₃⁺  while it increases for BCIF₂⁺, BCl₂F⁺ and BF₃⁺, the latter showing a particularly strong increase.

The line chart displays the intensity of AlCl₂⁺ and AlCl₃⁺ as a function of temperature. Both intensities increase with temperature, with AlCl₂⁺ showing a steeper rise than AlCl₃⁺.

| Temperature (°C) | BCl₃⁺ | BCIF₂⁺ | BCl₂F⁺ | BF₃⁺ |
|----------------|-------|--------|---------|-------|
| 0             |  200  |  40    |    0    |   0   |
| 100           |  160   |  40     |    20    |   10   |
| 200           |  150   |  40     |   20     |   20   |
| 300           |  80   |   100   |    80    |   100   |
| 400           |  -   |   -   |    -    |   -   |

| Temperature (°C) | AlCl₂⁺ | AlCl₃⁺ |
|----------------|--------|--------|
| 0              | 0      | 0      |
| 100            | 0     | 0     |
| 200            | 0    | 0     |
| 300            | 200    | 80     |
| 400            | -    | -     |

Answer: The boron species originate from ligand-exchange reactions.

Answer: This is a ligand-exchange reaction that leads to F/Cl transfer and the formation of Cl in the AlF3 powder.

Answer: The intensity of both etch products remains constant at 0 mV until 200 °C. After this point, the peak intensity increases for both products.

Answer: As can be seen in the subfigure b, the ACl2+ shows a higher peak intensity.

icdar2026-competition-data/test/gold_standard_test_set/atomic-layer-etching/experimental-usecase/20/Thermal Atomic Layer Etching of Aluminum Nitride.pdf


Fig. 4. Self-limiting behavior for CoO thermal ALE for long Hacac and  $\mathrm{O_3}$  exposures at  $250^{\circ}C$  Hacac exposure time was varied with  $\mathrm{O_3}$  exposure fixed at  $1.0~\mathrm{s}$ $\mathrm{O_3}$  exposure time was varied with Hacac exposure fixed at  $1.5~\mathrm{s}$

The figure shows the etch rate of CoOₓ (Å/cycle) as a function of exposure time to Hacac or O₃ (s) at 250 °C with a 40 s purge. Both curves show an increase in the etch ratio as exposure time increases.

| Hacac or O₃ Exposure Times (s) | Hacac | O3 |
| --- | --- | --- |
| 0.0 | 0.0 | 0.0 |
| 0.5 | - | - |
| 1.0 | 0.36 | 0.44 |
| 1.5 | 0.44 | 0.46 |
| 2.0 | 0.46 | 0.48 |
| 2.5 | 0.48 | 0.52 |
| 3.0 | - | - |

Answer: The experiments were performed under 40 s of purge at 250 °C.

Answer: The CoOx etch rate increases for both cases as the exposure time increases.

Answer: After 2.5 s of exposure to Hacac or O3.

Answer: Yes

icdar2026-competition-data/test/gold_standard_test_set/atomic-layer-etching/experimental-usecase/21/Thermal atomic layer etching of CoO using acetylacetone and ozone.pdf


Fig. 4. (a) The atomic percentage of the etched  $\mathrm{Al}_2\mathrm{O}_3$  surface and (b) the  $\mathrm{Al / O}$  ratio of the etched surface of  $\mathrm{Al}_2\mathrm{O}_3$  measured by X-ray photoelectron spectroscopy (XPS) for the reference, the  $\mathrm{Al}_2\mathrm{O}_3$  etched by partial layer etching  $(\Theta_{\mathrm{Al - Cl / BCl - O}}< 1)$ , and the  $\mathrm{Al}_2\mathrm{O}_3$  etched by ALET  $(\Theta_{\mathrm{Al - Cl / BCl - O}} = 1)$ .

The line chart illustrates the atomic percentages of Al and O of the three samples.

The bar chart compares the Al/O ratio across three samples: Ref., Partial Layer Etching, and ALET.

| Sample | Atomic Percentage Al | Atomic Percentage O |
|---|---|---|
| Ref. | 35 | 65 |
| Partial Layer Etching | 30 | 70 |
| ALET | 35 | 65 |

| Sample | Al/O Ratio |
|---|---|
| Ref. | 0.55 |
| Partial Layer Etching | 0.4 |
| ALET | 0.55 |

Answer: Approximately 1 nm.

Answer: The ALD Al2O3 reference has an Al/O ratio lower than 0.67, whilst sapphire is exactly 0.67.

Answer: Under partial layer etching, the Al/O ratio decreases below the reference value, indicating non-stoichiometric surface modification.

Answer: Figure 4 shows that the surface stoichiometry of Al2O3 responds very differently to partial layer etching compared to ALET. Under partial layer etching conditions, the atomic percentages shift and the Al/O ratio becomes lower than that of the ALD reference film. This suggests that the process removes oxygen and aluminum unevenly, likely due to preferential etching of surface-exposed sites. In contrast, when ALET is performed at a reactant ratio of unity, the surface stoichiometry remains unchanged. Both the elemental percentages and the Al/O ratio match the reference, showing that a complete monolayer is removed in each cycle without perturbing the underlying material.

icdar2026-competition-data/test/gold_standard_test_set/atomic-layer-etching/experimental-usecase/27/Atomic layer etching of Al2O3 using BCl3Ar.pdf