Temperature Dependence Modeling for MOS VLSI Circuit Simulation

An accurate and efficient temperature modeling methodology for the semi-empirical BSIM (Berkeley Short-Channel IGFET Model) has been developed for MOS VLSI circuit simulation. A sensitive model parameter subset which has large effects on transistor output characteristics is determined from the sensitivity analysis. Updating of model parameter values for this sensitive subset is performed prior to circuit simulation at each given temperature. For a 1.2-μm CMOS process, the sensitive subset for temperature effects consists of only eight out of the sixty-seven BSIM parameters. Circuit simulation using this sensitive subset approach to predict temperature effects has shown good agreement with experimental data on transistor output characteristics, inverter transfer characteristics, and oscillation frequency of a 31-stage ring oscillator.