Hi @Tim Edwards , if i create a subcell and instantiate ,the boundary seems not to cover farthest layer dimensions , and leave some spacing -- what could be the reason ? Thanks

I think you need to set the

FIXED_BBOX

property to the dimensions you want. See https://skywater-pdk.slack.com/archives/C016YSAP6TZ/p1638448693130800

@Ryan R: The default bounding box can be affected by various things you don't have control over and have nothing to do with the mask data bounds, such as DRC errors or labels. As Mitch mentioned, if you want the bounding box to be in a specific position, use the FIXED_BBOX property. Set the cursor box to the exact position you want the bounding box to be and type

box values

to get the four bounding box coordinate values in magic's internal grid units, then supply that string of values, in quotes, to the

property FIXED_BBOX

command.