DRC of metal fill after fill generation

[jeffdi]

A separate klayout DRC deck is needed to check the following

metal fill layer only

1. minimum area
2. minimum hole area
3. minimum space and notch
4. minimum width

metal fill interaction with metal drawing

1. minimum space to large metal
2. metal.fill is not overlapping metal.dg

Due to the number of shapes should have the ability to run each metal in a separate job.