Theory of defect scattering in two-dimensional multisubband electronic systems on III-V compound semiconductors

A theory of defect scattering has been developed for two-dimensional electron gas in metal-insulator-semiconductor field-effect transistors (MISFETs) on III-V compound semiconductors. An analytic formula has been obtained for the transport relaxation time limited by the defect scattering with intra- and intersubband transitions. The theory has been able to phenomenologically explain the experimental results for temperature dependence and Ninv (inversion electron concentration) dependence of the mobility on InAs and InP MISFETs. The abrupt decrease observed in the mobility at 1.2×1012 cm−2 of Ninv on InAs has been found to be due to the intersubband defect-scattering effect on ground subband electrons.