drc error.. errors:Metal2 coverage must be larger than 30% e

[sarathmandepudi]

drc error..

I was applied drc for one standard cell that will gives errors:Metal2 coverage must be larger than 30% entire chip and also Metal6.It will shows whole surface of cell as in circle.Please give the reply for that problem.Also gives to METAL2,6 for...coverage must be larger than 25% every 500*500um square.I am using Tanner tools,Hyper is for DRC verification.

 

[erikl]

drc error..

See your process design rules. If (poly and) metal coverage is less than the required minimum values, additional dummies must be provided. Automatic procedures should be available which provide such dummies. This is often done during pattern generation for the mask set.

 

[mnluan]

drc error..

If you check metal density just for one standard cell , the error can be ignored. The metal density rule constrains metal coverage in whole chip.
you can fill dummies to meet the request.

 

[hock]

Re: drc error..

sounds like ams hit-kit rule file. this rule is for shielding purpose.for a small design you can turn it off.

hock

 

[sarathmandepudi]

Re: drc error..

Thanks for reply....i will see....