First-principles study on energetics of intrinsic point defects in LaAlO3

Xin Luo, Biao Wang, Yue Zheng

Research output: Journal article publicationJournal articleAcademic researchpeer-review

64 Citations (Scopus)

Abstract

Using density-functional theory (DFT) calculations, the formation energies, electron affinities and electronic levels of various intrinsic defects in bulk LaAlO3 are investigated. Results give the atomic structures of charged interstitials, vacancies, Frenkel pairs, antisite defects, and Schottky defects, respectively. It is found that the formation energies of O vacancy are the lowest in the reducing conditions. In contrast, the La vacancy VLa is more favorable in formation energy as the O chemical potential increasing. Moreover, by considering the defect levels of LaAlO3 with respect to the silicon conduction bands, the effects of the electron and hole trapping in real devices are also simulated. Our results show that the paired charged VO, which lies in the middle of the silicon band gap, should be the key problematic defect. The deep defect level of VO can induce a large-tunneling-leakage current and cause instability in the device performance. These predictions provide rich defect structures in LaAlO3 and useful information for the microelectronic designs.
Original languageEnglish
Article number104115
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume80
Issue number10
DOIs
Publication statusPublished - 24 Sep 2009

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

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