High dopant and carrier concentration effects in gallium arsenide: Band structure and effective intrinsic carrier concentrations

Abstract

The quality and reliability of predictions from numerical simulations of GaAs/AlGaAs devices, such as heterojunction bipolar transistors, depend on model parameters. These parameters include the variations with doping and carrier concentrations of the valence- and conduction-band edges and of the effective intrinsic carrier concentrations for heavily doped p- and n-type gallium arsenide. The Klauder self-energy method is used to calculate the effects of interactions among carriers and dopant ions in heavily doped GaAs at 300 K. The carrier-carrier interactions of exchange and correlation are estimated by interpreting optical-absorption measurements and by calculations based on degenerate theory. When densities exceed 1019 cm−3 in p-type and 1017 cm−3 in n-type gallium arsenide, carrier-dopant ion interactions and carrier-carrier interactions become of the same order of magnitude and should be included in calculations of band-structure changes and of properties which depend on the density of states, such as carrier transport and effective intrinsic carrier concentrations.