Hi.. I was trying to import the sky130_fd_pr__nfet_03v3_nvt model spice file to layout. But I am getting guard rings for each standard cells. I can not remove the guard rings for each component. Is it necessary to keep guard rings for each component.? If not how can I remove that? I tried to draw it manually, but it is getting exported as 1.8v nfet spice file. I need 3.3v nfet. Please suggest a solution.

@Vyshnav P Dinesh are you working in magic or klayout? Have you tried using the device generator?

i am working in magic

(1) Once you import from SPICE, each device is in its own subcell created by the device generator. Click

i

on the subcell to select the instance and type

ctrl-p

to bring up the dialog of options. There is a checkbox for the guard ring that you can deselect. (2) If you draw by hand, then "mvdiffusion" + "poly" overlapping will be replaced with type "mvnfet", which is not the NVT type, as you mentioned. But you can just paint over the gate with type "nnfet" (note that "nnfet" is a thick-oxide device and so is compatible with "mvdiffusion" only, not "diffusion").