Closed-form electric-field profile model for AlGaAs/GaAs heterostructures

We propose a closed-form analytical model to describe the electric-field profile inside the GaAs layer of a modulation-doped AlGaAs/GaAs heterostructure. Derived from an accurate two-dimensional electron gas density expression, this model serves as a tool in the simulation of field effects on the spectral response of AlGaAs/GaAs metal-semiconductor-metal photodetectors. It is also suitable for analyzing surface field effects on lateral confinement mechanisms in mobility calculations for enhancement-mode heterostructure-based transistors. Results from this analytical expression are shown to agree well with numerical simulations performed on a physical device simulator and a modified self-consistent solution of Schrodinger and Poisson equations. (C) 2002 American Institute of Physics.