I am trying to design a small standard cell library with 90nm cells.Can someone can give me pointers on how to write my own DRC rules for 90nm and also the technology file that is given to cadence virtuoso as input.If I have DRC rules for 180nm and 350nm, how can I modify them for 90nm. More importantly where does one get the technology files for these advanced technologies.I think even the display files get modified for supporting many more metal layers dont they?

Can someone help me with this. Thanks.