Berlin 2015 – scientific programme

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HL: Fachverband Halbleiterphysik

HL 51: Focus Session: Role of polarization fields in nitride devices II

HL 51.1: Talk

Wednesday, March 18, 2015, 15:00–15:15, ER 164

Nitrogen vacancies in III-V nitrides as non-radiative recombination centers: a first-principles investigation — •Ying Cui, Christoph Freysoldt, and Jörg Neugebauer — Max-Planck-Institut für Eisenforschung, Max-Planck-Str. 1, 40627 Düsseldorf

For LED technology, one of the unresolved problems is the nature of the non-radiative recombination processes. Theoretical calculations could be an ideal subsidiary to experiment to identify possible non-radiative recombination centers in LEDs where point defects are usually hard to detect. Here, we show an efficient and reliable strategy to study non-radiative recombination centers in III-V nitrides based on density functional theory with the HSE hybrid functional. Our calculations locate the transition state in the capture process by using defect level occupation as a natural reaction coordinate. We compare the results for nitrogen vacancies in the AlN-GaN-InN series and find that they are always efficient non-radiative recombination centers. Systematic trends along the series and implications for alloys are discussed.