Analytical formulae for d.c. hopping conductivity degenerate hopping in wide bands

Abstract

Analytical formulae for d.c. hopping conductivities are derived for degenerate hopping in wide energy bands. The formulae are in good agreement with computer data for two- and three-dimensional systems. For impurity conduction in n-type crystalline Ge they give hopping conductivities within a factor of four of those observed experimentally. The formulae are also used to analyse T ^1/4 data in amorphous Ge and T ^1/3 data obtained from studies of inversion layers in MOSFET devices. In both cases, reasonable values for the system parameters are deduced.