As part of a Special Issue in Honor of 30 years of the American Vacuum Society’s Nellie Yeoh Whetten Award, this Invited Perspective discusses results and trends from the authors’ and other published research on metal contacts to β-Ga₂O₃, (4H and 6H)-SiC, nanocrystalline diamond (NCD), and nanocrystalline thin films and single-crystalline nanoribbons of α-SnS. The paper is not a comprehensive review of research on contacts to each of these semiconductors; it is instead a perspective that focuses on Schottky barrier height (Φ_b) measurements and factors that affect Φ_b, such as metal work function (Φ_m) and crystallographic surface plane. Metals and the associated processing conditions that form ohmic or Schottky contacts to each of these semiconductors are also described. Estimates of the index of interface behavior, S, which measures the dependence of Φ_b on Φ_m, show large variations both among different semiconductors (e.g., S ∼ 0.3 for NCD and S ∼ 1.0 for SnS nanoribbons) and between different surface planes of the same semiconductor [e.g., ($\overline{2}01$) vs (100) Ga₂O₃]. The results indicate that Φ_b is strongly affected by the nature of the semiconductor surface and near-surface region and suggest that the sharp distinction between covalent and ionic semiconductors as described in seminal theories can be adjustable.

中文翻译：

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金属-半导体接触研究的观点：Ga2O3，SiC，（纳米）金刚石和SnS的例子

作为30年的美国真空学会的尼尔森杨紫琼惠滕奖的荣誉特刊的一部分，这个邀请角度讨论从作者和金属接触到其他已发表的研究成果和发展趋势的β-Ga ₂ Ø ₃，（4H和6H）-SiC，纳米晶体金刚石（NCD）以及α-SnS的纳米晶体薄膜和单晶纳米带。本文不是对与每种半导体接触的研究的全面综述。它是而不是集中在肖特基势垒高度的立体（Φ _b影响Φ）测量和因素_b，如金属的功函数（Φ_米）和结晶表面。还描述了与这些半导体中的每一个形成欧姆或肖特基接触的金属和相关的处理条件。的界面行为，S，其测量Φ的依赖性的指标的估计_b上Φ_米，同时显示不同的半导体（例如，S〜0.3为NCD和S〜1.0的SnS纳米带）之间的不同的表面平面中的大的变化相同的半导体[例如，（$\overline{2}01$）vs（100）Ga ₂ O ₃ ]。结果表明，Φ _b强烈地受到半导体表面和表面附近区域的性质的影响，并建议在开创性的理论描述共价键和离子半导体之间的明显区别是可调节的。