Core model for independent multigate MOSFETs

This chapter presents the core model for the industry standard compact model BSIM-IMG, a fully featured turn-key compact model for independent multigate MOSFETs. The two independent (front and back gates) controls of the channel charge in these devices enable novel applications wherein the back gate can be in depletion or inversion, and BSIM-IMG accurately models these scenarios. Modeling of the channel charge in this device requires a consistent solution of coupled Poisson’s equations at the front and the back gate. This chapter presents an analytical solution for the Poisson’s equation which is numerically robust and passes important quality tests for an industry grade compact model. To represent real device effects, several extra models are later incorporated, such as drain-induced barrier lowering, velocity saturation, short-channel effects, self-heating effect, mobility-field dependence, and substrate-depletion effect.