We report high quality GeSn/GaAs heterostructure photodetectors grown by a modified magnetron sputtering system. A metal-semiconductor-metal photoconductor is fabricated to examine the ability of photodetection for GeSn alloy. Then the GeSn/GaAs heterostructure photodetector is first demonstrated with a detectivity of $1.8\times 10^{9}$ Jones achieved at 1450 nm under an applied reverse voltage bias of −0.1 V, which is comparable to or even better than the GeSn-based photodetectors grown by chemical vapor deposition. The work provides an alternative technique for low cost and large-area fabrication of GeSn based devices.

中文翻译：

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磁控溅射的 GeSn/GaAs 异质结构

我们报告了通过改进的磁控溅射系统生长的高质量 GeSn/GaAs 异质结构光电探测器。制造金属-半导体-金属光电导体以检验GeSn合金的光电探测能力。然后首先展示了 GeSn/GaAs 异质结构光电探测器，其探测率为 $1.8\乘以 10^{9}$ Jones 在施加 -0.1 V 的反向偏压下达到 1450 nm，这与通过化学气相沉积生长的基于 GeSn 的光电探测器相当甚至更好。这项工作为低成本和大面积制造基于 GeSn 的器件提供了一种替代技术。