The first letter is 'X'. This implies XMN0 is a subckt call statement calling a subckt named NCH. Search the netlist to find
.subckt NCH ...
You can find what MF and OS means.
It is probably loaded elsewhere by the spice files. Check for the files loaded to run with the netlist as well. X is for sub-circuit and M is for MOSFET.
The only included file in this netlist is TSMC025.lib,no others.
We usually name MOSFET as M**,but this netlist with XM** running successfully in simulation.
I didn't find any XM** definition in the PDK of TSMC 0.25.
It is strange.
Yes,u r right.i find NCH in the lib.
Why he/she use XM** but not M*?
Because he/she can use MF & OS only with XM**?
If so,what does OS mean?There is no explanation about OS in the lib.
Using XM rather M is to include some parasitic devices into the mosfet model.
Since MF and OS are not standard MOSFET model parameters, I recomended you to post here the NCH subckt definition in order to find what MF and OS mean exactly.
Just post the section from
.subckt NCH
or
.macro NCH
to
.ends