Distribution functions and fluid variables in a semiconductor

Abstract

Fluid dynamic variables for charge-carrier transport in a semiconductor in the presence of an electric field are constructed from a recently derived distribution. This distribution is relevant to processes in a semiconductor where the deformation-potential interaction dominates. Fluid variables thus found are compared to those obtained from a shifted Fermi–Dirac distribution. In the limit of zero electric field both distributions give identical results. Analytic corrections to Fermi–Dirac variables are obtained by expanding the new variables about small electric field. Corrections at higher electric field are found numerically. Among other results it is found that at sufficiently high electric field, drift velocity grows insensitive to charge-carrier concentration. A discussion is included of the appropriate expression for electron temperature in a semiconductor.