Abstract The Hall Van-der-Pauw method is widely used to assess the electrical properties of GaSb based semiconductor layers. Semi-insulating GaSb substrates are not available, and therefore, Hall structures are generally grown on semi-insulating GaAs. The lattice mismatch of 7.8% between GaAs and GaSb results in high defect densities, which may influence the measurement. We investigated an alternative approach for Hall effect measurements using a p-n junction for the electrical isolation of the test layer from layers below. This allows antimonide based test layers with low defect density grown lattice-matched on GaSb substrates to be analyzed. Negligible leakage currents across the p-n junctions are key to ensure significant measurement results. n- and p-GaSb layers show similar carrier concentration if grown on GaSb or semi-insulating GaAs, with the exception of highly n-doped layers >5 x 1017 cm−3. However, majority carrier mobilities were systematically higher on GaSb substrate, explained by a lower density of structural defects. Furthermore, the sample design with p-n junction enabled Hall effect measurements of quaternary p-Al0.2Ga0.8As0.02Sb0.98 layers, which was impossible for those same layers grown on GaAs due to strain induced phase-separation. The methodology is presented for antimonides, but it is applicable to a wide range of material systems including metamorphic structures.

中文翻译：

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使用 GaSb 衬底上的 pn 结对外延 GaSb 和 AlGaAsSb 层进行霍尔表征

摘要 Hall Van-der-Pauw 方法被广泛用于评估 GaSb 基半导体层的电性能。没有半绝缘 GaSb 衬底，因此霍尔结构通常生长在半绝缘 GaAs 上。GaAs 和 GaSb 之间 7.8% 的晶格失配导致高缺陷密度，这可能会影响测量。我们研究了另一种霍尔效应测量方法，使用 pn 结将测试层与下面的层电隔离。这允许分析在 GaSb 衬底上具有低缺陷密度生长晶格匹配的锑化物基测试层。穿过 pn 结的可忽略的泄漏电流是确保显着测量结果的关键。如果生长在 GaSb 或半绝缘 GaAs 上，n-和 p-GaSb 层显示出相似的载流子浓度，除了 >5 x 1017 cm-3 的高度 n 掺杂层。然而，GaSb 衬底上的多数载流子迁移率系统地较高，这是由较低的结构缺陷密度解释的。此外，具有 pn 结的样本设计能够对四元 p-Al0.2Ga0.8As0.02Sb0.98 层进行霍尔效应测量，这对于在 GaAs 上生长的相同层而言是不可能的，因为应变引起的相分离。该方法是针对锑化物提出的，但它适用于包括变质结构在内的各种材料系统。8As0.02Sb0.98 层，由于应变引起的相分离，这对于在 GaAs 上生长的相同层是不可能的。该方法是针对锑化物提出的，但它适用于包括变质结构在内的各种材料系统。8As0.02Sb0.98 层，由于应变引起的相分离，这对于在 GaAs 上生长的相同层是不可能的。该方法是针对锑化物提出的，但它适用于包括变质结构在内的各种材料系统。