Semiconductor Device Modeling Group

The Semiconductor Device Modeling group of the MSCAD (Mixed-Signal Computer-Aided Design) Laboratory develops compact models for both low and high power semiconductor devices. Compact models are developed using Hardware Description Languages (HDLs) such as Verilog-A and MAST. These models are physics-based and they accurately describe the electrical and thermal behavior of the device without sacrificing the simulation speeds of application circuits based off of these models. Compact models help circuit designers evaluate their designs through high performance simulations using industry standard simulation engines such as Spectre, HSPICE, Saber, etc.

The Semiconductor Modeling Group’s efforts have involved silicon, silicon carbide and gallium nitride material systems. In some cases, research efforts have involved modifications to existing industry standard models such as BSIM3, BSIM3SOI, BSIM4, Mextram, VBIC, MM20, etc. In other cases, the models have been derived from physics principles and implemented in compact form using various techniques such as charge control, lumped-charge, and Fourier methods. Some models have utilized quasi-static approximations, while most demand a non-quasi-static formulation for adequately representing the charge distribution in a lightly-doped drift layer commonly found in power semiconductor devices.

Our group places an emphasis on device characterization and model parameter extraction from these experimental measurements. As such, all device models have a proven characterization procedure. Further, each model is hardware-validated to ensure its fidelity in predicting device behavior observed in experimental measurements. The models are also subjected to exercise in application circuits as a way of ascertaining and addressing any numerical convergence issues.