skywater130
Skywater130 primitives for BAG.
These primitives are updated for V2.0.0 of the PDK. It currently support layout generation and LVS using Virtuoso pcells, which was previously not supported. Simulations using BAG is also supported.
This workspace and tech plugin are primarily maintained by Ayan Biswas, Felicia Guo, Sean Huang, and Bob Zhou.
Technology features and hints
- Layout resolution is in 5nm.
- Min channel length is 150nm, so min channel units is 30.
- This tech has standard, lvt, and hvt devices. pch hvt and lvt have min channel length of 350um, so they cannot be used for logic-style MOS with nch.
- Min nch width is 420nm (84 units). Min pch width is 550nm (110 units).
- Widths are quantized in irregular intervals. See the pcells for examples.
- Nch has 840nm. Pch has 1120nm.
- This tech has 5 metal layers and an “M0” (LI) layer.
- This tech has pcell MOM caps. M1-M2 caps provide ~0.4 fF / um^2. M1-M4 caps provide ~0.74 fF / um^2.
- This tech has pcell MIM caps, between M3-M4 and M4-M5. Both provide ~2.2 fF / um^2.
SD pitch: 0.430 um ~ 86 units. BAG quantizes vertical metal pitches to match the SD pitch ~ li, met2, met4
Metal min width and space (um): li : 0.170, 0.170 met1: 0.140, 0.140 met2: 0.140, 0.140 met3: 0.300, 0.300 met4: 0.300, 0.300 met5: 1.600, 1.600
Track manager hints:
- m4 needs to be at least w=5 to connect to m5
Resistors
- This tech has two flavors of “precisions” poly resistors: hrpoly (300 ohm / sq) and uhrpoly (2K ohm / sq). Min width is 0.33 um / 66 units, min resistor length is 0.5 um / 100 units. The contacts have a 2.16um length, required by DRC, so the min overall length is 4.82um.
res_type: standard ~ hrpoly
Width selection
- For nice compatibility with the routing grid, make the unit cell width quantized to the sd pitch ~ 430 nm / 86 units. (not a hard requirement)
- LR edges account for up to an additional 780nm / 156 unit
- Some good values: 102, 360, 532
Length selection
- To minimize unused area, quantize unit height to sd pitch ~ 86 for working with the routing grid. (not a hard requirement)
- Otherwise, unit height will round up to the next pitch of 86
- TB edges, including taps, account for up to 5.530 um / 1106 units
- Some good values: 270, 614
Abstract Generation
Abstract generation in this technology does not work out of the box. More details in this README.
Extraction
- This tech uses Calibre xRC for extraction. See $PDK_HOME/PEX/xRC and the manual for details.
- The xRC SVRF is set up to produce SPF files, to match other PEX tools. It can produce Spectre-format PEX netlists, but this has not been tested rigorously.
- xRC automatically capitalizes cell names, so top level cell names need to be full capitalized.
Licensing
This library is licensed under the Apache-2.0 license. See here for full text of the Apache license.
