A first-principles understanding of point defects and impurities in GaN

Attaining control over the electrical conductivity of gallium nitride through impurity doping is one of the foremost achievements in semiconductor science. Yet, unwanted contaminants and point defects continue to limit device performance, and experimental techniques alone are insufficient for elucidating the behavior of these unintentionally incorporated species. Methodological advancements have made first-principles calculations more powerful than ever and capable of quantitative predictions, though care must still be taken in comparing results from theory and experiment. In this Tutorial, we explain the basic concepts that define the behavior of dopants, unintentional impurities, and point defects in GaN. We also describe how to interpret experimental results in the context of theoretical calculations and also discuss how the properties of defects and impurities vary in III-nitride alloys. Finally, we examine how the physics of defects and impurities in GaN is relevant for understanding other wide-bandgap semiconductor materials, such as the II-IV-nitrides, boron nitride, and the transition metal nitrides.

Automated summary

Controlling electrical conductivity of gallium nitride through impurity doping is a significant achievement in semiconductor science, but challenges remain due to unwanted contaminants and point defects limiting device performance. Methodological advancements have made first-principles calculations more powerful for quantitative predictions, emphasizing the need for cautious comparison between theory and experiment. This tutorial explains basic concepts of dopants, unintentional impurities, and point defects in GaN, and discusses the interpretation of experimental results in the context of theoretical calculations.