What is the minimum size of via4, actually? The d...
# sky130y
Yuan Mei
03/29/2023, 1:21 AMWhat is the minimum size of via4, actually? The documentation https://antmicro-skywater-pdk-docs.readthedocs.io/en/latest/rules/periphery.html#via4 says 0.8um, but
magic:drc why via4 width < 1.18um (via4.1 + 2*via4.4)j
Jecel Assumpção Jr
03/29/2023, 1:31 AMvia4.1=0.800µm and via4.4=0.190µm, so the equation via4.1+2*via4.4 adds up to 1.180µm
Jecel Assumpção Jr
03/29/2023, 1:33 AMnote that the magic via4 layer is a logical thing and includes both the hole (via4.1) and the surrounding metal4 (via4.4 on both sides). When editing in magic you only see a big square, but when you generate the GDS file you will see a smaller square inside a big square
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Yuan Mei
03/29/2023, 1:41 AMOK, so the physical hole (the pillar between layers) is 0.8um W/L. extra 0.19um on each side is needed there to make contacts. Then, the hole-edge to hole-edge spacing can be as small as 0.8um according to
via4.2