18. First-Principles Calculations 2

Gallium oxide has rapidly developed as a prime candidate for next-generation power electronics owing to the availability of high-quality material (e.g., large single-crystal substrates and epitaxial films) in conjunction with its favorable optical and electronic properties. While a number of advances have been made in improving the crystal quality, improving control over the free carrier and defect concentrations in this wide-band gap semiconductor are critical to realize the full potential of Ga\(_2\)O\(_3\)-based devices. Identifying the most suitable dopants and the origins of the prominent deep-level defects, as well as possible passivation techniques, is therefore an essential next step in further developments. In this chapter, we use hybrid functional calculations to investigate the behavior of a number of native defects, candidate dopants, and extrinsic impurities in \(\upbeta \)-Ga\(_2\)O\(_3\) and to elucidate how theory has helped in understanding the defect-related properties of this material.