First-principles study of the influence of Nb doping on the electronic structure and optoelectronic properties of β-Ga2O3

The electronic structure and optoelectronic properties of Nb-doped beta-Ga(2)O(3)were investigated by using plane wave ultrasoft pseudopotential generalized gradient approximation +U (GGA + U) method based on density functional theory. Four supercell models, namely, Ga23O36Nb1, Ga32O48, Ga39O60Nb1, and Ga47O72Nb1, were constructed. Results show that the formation energy of the doped system is lower and has higher stability under Ga-rich conditions than in O-rich conditions. With the increment in Nb doping concentration, the formation energy and lattice constant gradually increase, the stability of the system gradually decreases, and the band gap of the system gradually narrows. As the doping concentration increase, the absorption intensity increases. Furthermore, the increasing doping concentration accelerates the separation of holes and electrons, prolongs the carrier lifetime, and enhances conductivity. These conclusions provide a certain theoretical basis for the wide application of beta-Ga2O3. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

The electronic structure and optoelectronic properties of Nb-doped beta-Ga(2)O(3) were investigated using the GGA + U method based on density functional theory. It was found that the system exhibited higher stability under Ga-rich conditions and that the stability decreased and the band gap narrowed with increasing Nb doping concentration.