Physical modeling of MOS-controlled high-voltage devices for integrated circuit computer-aided design.

摘要

This dissertation presents methodology for physical charge-based modeling of MOS-controlled high-voltage (HV) devices for integrated circuit (HVIC) computer-aided design (CAD). New models for two different MOS-controlled HV devices, the insulated-gate-bipolar transistor (IGBT) and the double-diffused MOS transistor (DMOST), are developed. The effects of the buffer layer and static/dynamic latch-up in the IGBT are characterized, and quasi-saturation, space-charge-limited current flow, and effects of the inherent BJT in both vertical and lateral DMOSTs are modeled. These effects, which are not properly represented in conventional equivalent-(sub)circuit models, are physically and sometimes semi-numerically accounted for in our models. Two-dimensional numerical device simulations were used extensively to study the effects and to aid the model development.;The developed models are implemented in the circuit simulator 9P ICE via FORTRAN subroutines (UDCSs). With only known structural (device) parameters and crudely extracted model parameters, device/circuit simulations favorably predicted measured characteristics of test devices. The models in SPICE provide a capability of mixed-mode device/circuit simulation, which is not afforded by other equivalent-(sub)circuit models, and hence can facilitate computer-aided optimal device/circuit design of HVICs.