How to identify the Threshold Voltage of transistor model?

- November 21, 2023 at 3:25 pm
  
  Julio Mariano Geronimo
  Subscriber
  
  Hi, I am using the transistor model level 66 HiSim 2.0 NMOS MOSFET. Below is the model datasheet:
  
  When searching the model datasheet, there is no information regarding the threshold voltage of the transistor. May I know how then should I determine the transistor threshold voltage?
- November 27, 2023 at 4:54 pm
  
  Dan Dv
  Ansys Employee
  
  Hello Julio,
  According to the HiSim manual,
  "Different from the drift approximation (see for example Eq. (30)), the drift-di usion approximation does
  not require a threshold voltage parameter Vth for describing device performances. The MOSFET device
  parameters such as the oxide thickness TOX and the substrate doping concentration NSUBC
  determine the complete MOSFET behavior including the subthreshold characteristics automatically and
  consistently."
  I'm not at libert to share the specific equations or specification directly (if so, we would publish them in the online help) but they can be downloaded from the the HiSim Research Center:
  HiSIM Download | HiSIM Research Center (hiroshima-u.ac.jp)
  You mentioned a data sheet, but your screen cap just shows our default model parameter set. Please note, that those values are set to mach the parameter defaults as defined by the HiSim model writers, and are not indicative of any physical semiconductor process. Typically you would be given in a data sheet, or more likely the model would be pre setup in a SPICE file, by the semiconductor model vendor themselves.
  Best regards,
  -Dan