Hybrid functional with semi-empirical van der Waals study of native defects in hexagonal BN

TL;DR

This study uses a hybrid functional with semi-empirical van der Waals corrections to analyze native defects in hexagonal BN, revealing defect stability and activity under various conditions.

Contribution

It combines hybrid DFT with empirical dispersion corrections to accurately predict defect formation energies and transition levels in hexagonal BN.

Findings

Interstitial B is most stable under N-rich and p-type conditions.

B vacancy and interstitial N dominate near the conduction band.

Defects are inactive due to deep ionization levels.

Abstract

The formation energies and transition energy levels of native defects in hexagonal BN have been studied by first-principles calculations based on hybrid density functional theory (DFT) together with an empirical dispersion correction of Grimme's DFT-D2 method. Our calculated results predict that the interstitial B is the most stable defect under N-rich and p-type conditions. While the B vacancy and interstitial N become the dominate defects when the electron chemical potential is near the conduction band maximum of host. Nevertheless, these compensating defects would be inactive due to their ultra deep ionization levels under both p- and n-type conditions.