I have SPICE BSIM2 parameters for a MOSIS process, and I also have the MOSIS BSIM3 parameters for the wafer lot that contained my design. Which parameters will give the more accurate simulations?
The University of California at Berkeley BSIM3 web site includes a comparison of the merits of BSIM2 and BSIM3. Which is more accurate? The answer to that question in any particular case depends on the particulars of the case (how accurate is the netlist, especially the parasitics, what are the critical circuit nodes and how well are they characterized, etc.). In general, BSIM3 CAN be more accurate, but in particular, if your circuit behavior depends on devices with geometries outside the range of focus of MOSIS parameter optimization strategies (currently dimensions less than 20 micrometers, but this is subject to change), then a binned set of BSIM2 parameters may be better. A comparison of simulation results using MOSIS BSIM3 parameters from several wafer lots can provide useful information about the effects of process variations on the performance of your design. 2.0 The header for the SPICE BSIM3v3 model cards posted on the MOSIS web pages says “SPICE BSIM3 Version 3.1 (HSPICE Leve
