DC model for BiMOS structure and its adaptation to a circuitsimulation environment

摘要

The objective was to develop a model that can accurately describenthe hybrid-mode operation of deep submicron LDD pMOSFETs in a circuitnsimulation environment. The device threshold voltage, various currentncomponents, transconductance, and output conductance are extractednexperimentally, modelled analytically, and adapted to meet the circuitnsimulation requirements. The latter necessitates that the modelnequations, together with their derivatives, be continuous. The effectsnof independently biasing the source, drain, gate, and body potentials onnthe device currents and parameters are highlighted. A criticalncomparison between the presented model XSIM and HSPICE is made. Thenresults show that unlike HSPICE, where the MOSFET and the bipolar devicenembedded in the structure have to be simulated as two entities, thensuggested model describes the composite structure as a single entity andnpredicts its behaviour accurately for a range of different channelnlengths based on a single set of process and device model parameters