Nickel oxide, in particular in its doped, semiconducting form, is an important component of several optoelectronic devices. Doping NiO is commonly achieved either by incorporation of lithium, which readily occupies Ni sites substitutionally, producing the LiNi acceptor, or by supplying reactive oxygen species during NiO film deposition, which leads to the formation of Ni vacancies (VNi). However, the energetic position of these acceptors in the NiO band gap has not been experimentally determined until today. In this work, we close this knowledge gap by studying rectifying np heterojunctions of NiO on top of fluorine-doped tin oxide. These structures show sufficient rectification to perform electric characterization by defect spectroscopic techniques, specifically capacitance-voltage and thermal admittance spectroscopy. Using these methods, the (0/−) charge transition levels are determined to be 190 meV and 409 meV above the valence band edge for the LiNi and the VNi acceptor, respectively.

中文翻译：

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鉴定掺杂氧化镍中的 LiNi 和 VNi 受体水平

氧化镍，特别是其掺杂的半导体形式，是几种光电器件的重要组成部分。NiO 的掺杂通常是通过掺入锂来实现的，锂很容易替代地占据 Ni 位点，产生 LiNi 受体，或者通过在 NiO 薄膜沉积过程中提供活性氧物质，从而导致 Ni 空位 (VNi) 的形成。然而，直到今天，这些受体在 NiO 带隙中的能量位置还没有通过实验确定。在这项工作中，我们通过研究在掺氟氧化锡顶部的 NiO 的整流 np 异质结来缩小这一知识差距。这些结构显示出足够的整流以通过缺陷光谱技术进行电学表征，特别是电容-电压和热导纳光谱。使用这些方法，