| # This directory contains a seal ring generator for the Googl/SkyWater |
| # sky130 PDK using magic. Because the seal ring contains many layers that |
| # do not appear in standard layout editing, they are all specially implemented |
| # in the sky130seal_ring.tech file in this directory. |
| # |
| # An example seal ring was generated by SkyWater and imported using magic's |
| # gdsquery.sh script. It was then hand-edited to contain only the bottom |
| # quarter. Then it was saved in .mag databases. |
| # |
| # The generator script sky130_gen_sealring.py calls magic using the |
| # sky130seal_ring.tech file, and automatically modifies the geometry to |
| # stretch to the half width and height of the specified dimensions. Then |
| # the lower-left cells are copied and folded over the centerline to make |
| # the complete seal ring. The seal ring is then written out in GDS format. |
| # Then a simplified magic view is generated in the usual user-facing |
| # sky130 technology file, with the GDS_FILE property pointing to the seal |
| # ring GDS. This layout and GDS can then be imported into a layout. |
| # |
| # Usage: |
| # |
| # sky130_gen_sealring.py width height target_dir [-force] [-outer] |
| # |
| # Where: |
| # width = the full-chip layout width |
| # height = the full-chip layout height |
| # target_dir = location of the full-chip layout |
| # |
| # -force = overwrite existing files in the target directory |
| # -outer = width and height represent the seal ring outer edge, not the chip area |
| # |
| # Results: |
| # Files advSeal_6u_gen.mag and advSeal_6um_gen.gds are generated and placed in |
| # target_dir. advSeal_6u_gen.mag is an "abstract" view that represents the |
| # seal ring in diffusion and the nikon cross in metal1, and references |
| # the advSeal_6um_gen.gds file in the same directory as a GDS_FILE property. |
| # |
| |
