Etude morphologique et caractérisation des alliages à base de nitrure

Abstract

The main objective in this work is to study the transport of charge carriers in semiconductor materials specifically boron nitride (BN), gallium nitride (GaN), aluminum nitride (AlN) and their ternary alloys BGaN and BAlN by the Monté Carlo method which it possible to reproduce the microscopic phenomena in semiconductor materials. The phenomenon of transport in these semiconductors results from the behavior of the electrons of the conduction band and the band gap. An analytical study of the problem requires knowledge of the electron energy distribution function, a function obtained by solving the Boltzmann equation. Because of its complexity, this partial differential equation has no analytical solution except in a limited number of cases. That is why other processes, in particular the Monte Carlo methods, have been used to address this whole problem. For this we have developed a program written in Fortran language based on the principle of this method. This program makes it possible to calculate the probabilities from the usual expressions, considering in our case a model with three valleys (Γ, L, X), isotropic but not parabolic, and to determine the evolution of the various interactions as well as the speed and the energy of the carriers in the two ternary materials BGaN and BAlN which do not essentially influence the behavior of the electron. They are nevertheless introduced to obtain a description as quantitative as possible of the electronic dynamics.