AN IMPROVED ELECTRON AND HOLE MOBILITY MODEL FOR GENERAL-PURPOSE DEVICE SIMULATION

A new, comprehensive, physically-based, semiempirical, local model for transverse-field dependent electron and hole mobility in MOS transist ors is presented, In order to accurately predict the measured relation ship between the effective mobility and effective electric field over a wide range of substrate doping and bias, we account for the dependen ce of surface roughness limited mobility on the inversion charge densi ty, in addition to including the effect of coulomb screening of impuri ties by charge carriers in the bulk mobility term, The result is a sin gle mobility model applicable throughout a generalized device structur e that gives good agreement with measured mobility data and measured M OS I-V characteristics over a wide range of substrate doping, channel length, transverse electric field, substrate bias, and temperature.