Generation of nonequilibrium carriers in the theory of the transverse impedance of semiconductor surface layers and in the field-effect theory

Abstract

Processes at the boundary between the space-charge region and the bulk of a semiconductor when ac current flows through this boundary are considered. It is shown that nonequilibrium carriers are generated not only when an inversion layer is formed at the surface but also when depletion or accumulation layers are formed. The theory of the transverse impedance of the surface layers and the field-effect is given, taking the generation of nonequilibrium carriers into account. The generation leads to the frequency dispersion of the transverse impedance and of the field-effect mobility both with an inversion and with depletion or accumulation layers, when the bulk conductivity of a semiconductor is close to the intrinsic one.