@Gabriel Maranhão: Process options have to be worked out with the foundry in advance. The choices for

gf180mcuD

are in some sense arbitrary and meant to support the Caravel chip, as that was what I was working on when developing the PDKs. If everyone has been designing to the

gf180mcuD

PDK, then the assumption is 5 metal layers, 1.1um thick top metal, and 1k high-res poly. I do not know what files say "Stack: 5LM with 9kA top metal thickness". That was true of

gf180mcuC

and what we used for the first GF open MPW (which caused GF to inform us that we shouldn't be using that process option set, even though it was listed in the documentation and nothing was mentioned in the documentation about it not being good). I am not aware of any issues in filling out the forms to reserve a tapeout, but then I didn't fill out those forms.