I would like to ask how accurate can the PTM be considered for characterization purposes?
Is there only one PTM for any supply voltage?or there should be several ones for different supply V?
I extracted the PTM for my technology on NANOCMOS but I am not sure about the parameters I chose.I put like Vth, the threshold voltage at my supply voltage of interest and not the one at 1,2 V as given from TSMC datasheet.
The threshold voltage Vth (in 1st approximation) doesn't depend on the supply voltage. But for good characterization you should try and get the correct Vth voltages for the used MOSFETs of your process.
The supply voltage can be changed/fixed in the SPICE file / analysis setUp.