| # Metal fill | |
| This module inserts floating metal fill shapes to meet metal density | |
| design rules while obeying DRC constraints. It is driven by a `json` | |
| configuration file. | |
| ## Commands | |
| ```{note} | |
| - Parameters in square brackets `[-param param]` are optional. | |
| - Parameters without square brackets `-param2 param2` are required. | |
| ``` | |
| ### Density Fill | |
| This command performs density fill to meet metal density DRC rules. | |
| ```tcl | |
| density_fill | |
| [-rules rules_file] | |
| [-area {lx ly ux uy}] | |
| ``` | |
| #### Options | |
| | Switch Name | Description | | |
| | ----- | ----- | | |
| | `-rules` | Specify `json` rule file. | | |
| | `-area` | Optional. If not specified, the core area will be used. | | |
| ## Example scripts | |
| The rules `json` file controls fill and you can see an example | |
| [here](https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts/blob/master/flow/platforms/sky130hd/fill.json). | |
| The schema for the `json` is: | |
| ```json | |
| { | |
| "layers": { | |
| "<group_name>": { | |
| "layers": "<list of integer gds layers>", | |
| "names": "<list of name strings>", | |
| "opc": { | |
| "datatype": "<list of integer gds datatypes>", | |
| "width": "<list of widths in microns>", | |
| "height": "<list of heightsin microns>", | |
| "space_to_fill": "<real: spacing between fills in microns>", | |
| "space_to_non_fill": "<real: spacing to non-fill shapes in microns>", | |
| "space_line_end": "<real: spacing to end of line in microns>" | |
| }, | |
| "non-opc": { | |
| "datatype": "<list of integer gds datatypes>", | |
| "width": "<list of widths in microns>", | |
| "height": "<list of heightsin microns>", | |
| "space_to_fill": "<real: spacing between fills in microns>", | |
| "space_to_non_fill": "<real: spacing to non-fill shapes in microns>" | |
| } | |
| }, ... | |
| } | |
| } | |
| ``` | |
| The `opc` section is optional depending on your process. | |
| The width/height lists are effectively parallel arrays of shapes to try | |
| in left to right order (generally larger to smaller). | |
| The layer grouping is for convenience. For example in some technologies many | |
| layers have similar rules so it is convenient to have a `Mx`, `Cx` group. | |
| This all started out in `klayout` so there are some obsolete fields that the | |
| parser accepts but ignores (e.g., `space_to_outline`). | |
| ## Regression tests | |
| There are a set of regression tests in `./test`. For more information, refer to this [section](../../README.md#regression-tests). | |
| Simply run the following script: | |
| ```shell | |
| ./test/regression | |
| ``` | |
| ## Limitations | |
| ## FAQs | |
| Check out [GitHub discussion](https://github.com/The-OpenROAD-Project/OpenROAD/discussions/categories/q-a?discussions_q=category%3AQ%26A+metal%20fill+in%3Atitle) | |
| about this tool. | |
| ## License | |
| BSD 3-Clause License. See [LICENSE](LICENSE) file. | |