AlN/GaN Superlattice band structure calculation Using Empirical Tight Binding Model

Abstract

AlN/GaN superlattices are studied using the empirical tight-binding method (ETBM) with sp³ approximation. The model includes first-nearest-neighbor orbital interactions and accounts for the strain effect by modifying the ETBM parameters based on variations in bond lengths and angles. According to the authors knowledge, this study marks the first application of ETBM to determine the full band structure of AlN/GaN superlattices. On average, the ETBM band gaps resulting from this work are 7.48 % closer to the experimental data in comparison with Kronig-Penney outputs. In addition to the high accuracy of the model, the presented model is easier to implement compared to the density functional theory model.