Influence of Molar Composition on Electron Mobility in Solid Solution AlGaAs

Abstract

The influence of the AlAs molar composition on the Hall electron mobility in the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{A}1_{x}\text{Ga}_{1-x}\text{AS}$</tex> solid solution is studied in this work. The simulation was carried out on the basis of a relaxation equations system for three valleys of semiconductor energy bands. The momentum relaxation times for various scattering mechanisms are obtained by averaging the electron scattering rate over the distribution function. The simulation results were functionally more than satisfactorily agreed with the experiment. Modeling by the method of relaxation equations made it possible to reveal a specific feature of the studied dependence <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mu(x)$</tex> in the form of a significant decrease in mobility (“dip”) in the range of values <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.44 &lt; x &lt; 0.48$</tex> . A set of initial simulation parameters has been defined, which makes it possible to obtain good agreement with the experimental results. The method is suitable for other ternary semiconductor compounds.