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Dummy filler

Generate the dummy filler script​

You will need to generate the dummy filler utility file by combining two existing files:

  • Dummy metal (DM):
    • ~/65NM_PDK_ZIP/65 MS RF GP/Utility/Mentor Graphics/tn65cldr001c3_2_5a/../Dummy_Metal_Calibre_65nm.25a
  • Dummy oxide definition / poly (DODPO):
    • ~/65NM_PDK_ZIP/65 MS RF GP/Utility/Mentor Graphics/tn65cldr001c2_2_5a/../Dummy_OD_PO_Calibre_65nm.25a

Copy these files into ~/ER_ASIC_Rev1/APR for ease of use. In the terminal, run the following command (which can also be found inside the DODPO file) to combine the two files:

cat Dummy_OD_PO_Calibre_65nm.24a Dummy_Metal_Calibre_65nm.24a > Dummy_OD_PO_Metal_Calibre_65nm.24a

In the resulting file, check that #DEFINE WithSealring and #DEFINE COMBINE_DODPO_DM are uncommented.

Run the dummy filler script on ASIC_Tapeout​

In the ASIC_Tapeout layout, navigate to Calibre → Run nmDRC. For the "Runset File Path," create a directory called "DRC" and select it, and choose a runset name (e.g., Dummy_Runset). The following image shows the DRC dialog:

Dummy Dialog

Note that the "DRC Options" tab may not automatically appear. You can open it by navigating to Setup → DRC Options. Make the following changes in the dialog:

  • Rules
    • DRC Rules File: ~/ER_ASIC_Rev1/APR/Dummy_OD_PO_Metal_Calibre_65nm.25a
    • LVS Run Directory: ~/Cadence/DRC
  • Outputs
    • Format: GDSII
    • Cell suffix: _DODPO_DM
  • DRC Options → Output
    • Max. errors generated per check: All
    • Max. vertices in output polygons: All

After these modifications, save the runset and select "Run DRC." Once DRC completes, a window will open with the results, and a GDSII file for the dummy filler has been generated.

From the main Virtuoso window, stream in the file ~/Cadence/DRC/ASIC_Tapeout.drc.results. You must ensure that the dummy filler has the correct coordinates with respect to the ASIC_Tapeout cell. Otherwise, you will encounter a DRC error (DM9.R.1). One way to do this is by opening the ASIC_Tapeout_DODPO_DM cell, navigating to Create → Shape → Rectangle, and creating a rectangle on the drawing "ref" layer from (0, 0) around the dummy filler.

In the ASIC_Tapeout layout, add in the dummy filler by selecting ASIC_Tapeout_DODPO_DM for the cell and line up the cell at exactly (0, 0) to match with the seal ring.

Final result (dummy filler)​

The following image shows the final result of the dummy filler for the ERASICv1:

Dummy Filler

The resolution of the display is turned to "Very High" for aesthetic purposes.

Final result (ASIC_Tapeout)​

The following image shows the final result of ASIC_Tapeout for the ERASICv1, which includes ASIC_ALL (which includes DigitalCorePads, the bond pads, and the bond pad labels), the seal ring, and the dummy filler:

ASIC_Tapeout