Re: Diff between well contact and substrate contact in 90nan
Hi Tama,
"... the nmos substrates is directly connected to vss ...".
So you should connect the substrate tie of your mim cap to vss.
There is a lot of way to deal with DNWELL in a deck depending on each tech.
Some deck define the DNWELL, the internal substrate and the external substrate.
Some just define the DNWELL and the external substrate.
Some uses both depending on the devices.
Some uses pins in the schematic, some uses just properties, some uses both, some have a special diode cell to define the dnwell, the external substrate and the internal substrate ...
So what I want to say is you should be really carefull of how your deck deals with DNWELL just to be sure to not do silly mistakes.
Anyway in your case of the mim cap, I think you want a PLAIN DNWELL under the cap and so the substrate tie is just here to define the EXTERNAL substrate which is in your case the substrate of your NMOS so VSS.
Franck.