# gdsfill  **gdsfill** is an open-source tool for inserting dummy metal fill into semiconductor layouts. It helps designers meet density requirements and prepare GDSII layouts for manufacturing by analyzing, erasing, and generating dummy fill patterns across multiple layers. The tool is designed to integrate easily into existing design flows and ensures reproducible, automated preparation of layouts before tape-out. This project is still under development. Please report any issues you encounter and always verify your layout before tape-out deadlines to prevent submission failures. ## Installation **gdsfill** is distributed as a Rust binary crate. Install it via `cargo`: ```text $ cargo install gdsfill ``` Rust 1.85 or later is required. If you don't have Rust installed, get it from [rustup.rs](https://rustup.rs). ## Supported Processes | `--process` | PDK | Layers | |------------------|------------------------------|--------------------------------------------| | `ihp-sg13g2` | IHP SG13G2 | Activ, GatPoly, Metal1-5, TopMetal1-2 | | `ihp-sg13cmos5l` | IHP SG13CMOS5L | Activ, GatPoly, Metal1-4, TopMetal1 | | `gf180mcuA` | GlobalFoundries GF180MCU (A) | COMP, Poly2, Metal1-3 (30K top) | | `gf180mcuB` | GlobalFoundries GF180MCU (B) | COMP, Poly2, Metal1-4 (11K top) | | `gf180mcuC` | GlobalFoundries GF180MCU (C) | COMP, Poly2, Metal1-5 (9K top) | | `gf180mcuD` | GlobalFoundries GF180MCU (D) | COMP, Poly2, Metal1-5 (11K top) | ## Density This command calculates the utilization per layer and prints the values. It is useful to check layer density before and after running the fill process: ```text gdsfill density ``` Both `density` and `fill` print one summary per layer. Add `--verbose` to also print the per-tile table. ## Erase If a layout already contains dummy fill, or if previous fills should be removed, this command erases all dummy metal fill from a layout: ```text gdsfill erase ``` ## Fill To insert dummy metal fill into all supported layers of a layout, run: ```text gdsfill fill ``` If you only want to simulate the process without modifying the layout file, use `--dry-run`: ```text gdsfill fill --dry-run ``` ## Custom Configuration By default, **gdsfill** inserts dummy metal fill into each layer using predefined parameters. To apply different parameters or restrict fill to specific layers, you can create a custom configuration file. The following example config inserts fill only into **TopMetal1** and **TopMetal2**: ```yaml PDK: ihp-sg13g2 layers: TopMetal1: algorithm: Square density: 60 deviation: 1 TopMetal2: algorithm: Square density: 60 deviation: 1 ``` > Example config files are available in `gdsfill/configs`. To use a custom config file, pass it with `--config-file`: ```text gdsfill fill --config-file ```