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arXiv · 2402.11162

Native defects and their complexes in spinel LiGa5O8: the puzzle of p-type doping

Klichchupong Dabsamut·Kaito Takahashi·Walter R. L. Lambrecht
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Abstract

Recently, LiGa$_5$O$_8$ was identified as a cubic spinel type ultra-wide-band-gap semiconductor with a gap of about 5.36 eV and reported to be unintentionally p-type. Here we present first-principles calculations of the native defects and various of their complexes to try to explain the occurrence of p-type doping. Although we find Li-vacancies to be somewhat shallower acceptors than in LiGaO$_2$, and becoming slightly shallower in complexes with donors such as V$_{\rm O}$ and Ga$_{\rm Li}$ antisites, these $V_{\rm Li}$ based defects are not sufficiently shallow to explain p-type doping. The dominant defects are donors and in equilibrium the Fermi level would be determined by compensation between donors and acceptors, and pinned deep in the gap.

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Klichchupong Dabsamut, Kaito Takahashi, Walter R. L. Lambrecht. 2024-02-17. Native defects and their complexes in spinel LiGa5O8: the puzzle of p-type doping. https://arxiv.org/abs/2402.11162

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