Precision determination of band offsets in strained InGaAs/GaAs quantum wells by C-V-profiling and Schroedinger-Poisson self-consistent simulation

TL;DR

This study combines C-V profiling and self-consistent Schroedinger-Poisson simulations to accurately determine conduction band offsets in strained InGaAs/GaAs quantum wells, providing a precise empirical formula.

Contribution

It introduces a combined experimental and numerical approach to precisely measure band offsets in strained quantum wells, deriving a specific empirical formula for DE_C(x).

Findings

Conduction band offsets follow the formula DE_C(x) = 0.814x - 0.21x^2.

Self-consistent Schroedinger-Poisson simulations match experimental C-V data.

Accurate band offset values for strained InGaAs/GaAs quantum wells are obtained.

Abstract

The results of measurements and numerical simulation of charge carrier distribution and energy states in strained quantum wells In_xGa_{1-x}As/GaAs (0.06 < x < 0.29) by C-V-profiling are presented. Precise values of conduction band offsets for these pseudomorphic QWs have been obtained by means of self-consistent solution of Schroedinger and Poisson equations and following fitting to experimental data. For the conduction band offsets in strained In_xGa_{1-x}As/GaAs - QWs the expression DE_C(x) = 0.814x - 0.21x^2 has been obtained.