Recent development on Ge1−xSnx nanowires with high Sn content, beyond its solid solubility limit, makes them attractive for all group-IV Si-integrated infrared photonics at the nanoscale. Herein, we report a chemical vapor deposition-grown high Sn-content Ge–Ge0.92Sn0.08 core–shell based single nanowire photodetector operating at the optical communication wavelength of 1.55 μm. The atomic concentration of Sn in nanowires has been studied using x-ray photoelectron and Raman spectroscopy data. A metal–semiconductor–metal based single nanowire photodetector, fabricated via an electron beam lithography process, exhibits significant room-temperature photoresponse even at zero bias. In addition to the high-crystalline quality and identical shell composition of the nanowire, the efficient collection of photogenerated carriers under an external electric field results in the superior responsivity and photoconductive gain as high as ∼70.8 A/W and ∼57, respectively, at an applied bias of −1.0 V. The extra-ordinary performance of the fabricated photodetector demonstrates the potential of GeSn nanowires for future Si CMOS compatible on-chip optical communication device applications.

中文翻译：

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Ge–Ge0.92Sn0.08 核壳单纳米线红外光电探测器，具有优异的片上光通信特性

Ge的最新进展1−x锡X具有高 Sn 含量的纳米线，超出其固溶度极限，使它们对纳米级的所有 IV 族硅集成红外光子学具有吸引力。在此，我们报告了化学气相沉积生长的高 Sn 含量 Ge-Ge0.92锡0.08基于核壳的单纳米线光电探测器在 1.55 μm 的光通信波长下工作。已经使用 x 射线光电子和拉曼光谱数据研究了纳米线中 Sn 的原子浓度。通过电子束光刻工艺制造的基于金属-半导体-金属的单纳米线光电探测器即使在零偏压下也表现出显着的室温光响应。除了纳米线的高结晶质量和相同的壳组成外，在外部电场下有效收集光生载流子导致优异的响应度和光电导增益分别高达~70.8 A / W和~57，分别为-1.0 V 的施加偏压。