How the power MOSFET inversion layer carriers' mobility and its thermal gradient affects the TC

This paper studies the mobility of the carriers in the inversion layer of the power MOSFET and how this affects the TC (thermal coefficient). All the scattering mechanisms that are involved in the inversion layer were considered to modeling the mobility. In particular, the effect of the transverse electrical field, phonons and the Coulomb scattering effects will be studied. Particular attention will be placed on the acoustic and optical phonon effects and on the carrier-carrier scattering, ionized impurity in the depletion region, oxide fixed charges and oxide-silicon interface charges effects. The paper also will treat the Lombardi unified model to explain the mobility in the inversion layer. New considerations on TC will be implemented and a real example will validate the model proposed. ©2007 IEEE.