What is the minimum size of via4 actually The documentation

Question

What 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` insists gt 1 18um ` drc why via4 width lt 1 18um via4 1 + 2 via4 4 ` I have already enclosed via4 with sufficient met4 and met5

Jecel Assumpção Jr · Answer

via4 1=0 800µm and via4 4=0 190µm so the equation via4 1+2 via4 4 adds up to 1 180µm

Jecel Assumpção Jr · Answer

note 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

Yuan Mei · Answer

OK 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` It makes sense now Thanks