High-Performance Silicon-Compatible Large-Area UV-to-Visible Broadband Photodetector Based on Integrated Lattice-Matched Type II Se/n-Si Heterojunctions
High-Performance Silicon-Compatible Large-Area UV-to-Visible Broadband Photodetector Based on Integrated Lattice-Matched Type II Se/n-Si Heterojunctions
复制标题
基于集成晶格匹配 II 型 Se/n-Si 异质结的高性能硅兼容大面积紫外可见宽带光电探测器
DOI：
10.1021/acs.nanolett.8b00988
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发表时间：
2018-08-01
期刊：
影响因子：
10.8
通讯作者：
Fang, Xiaosheng
中科院分区：
文献类型：
--
作者：
Yang, Wei;Hu, Kai;Fang, Xiaosheng
提出并开发了一种金诱导NH4Cl辅助蒸气基路线，以在晶格匹配的（111）取向硅衬底上实现垂直排列的亚微米Se晶体，并在此基础上构建高性能大面积硅兼容光电探测器。由于能带结构和强烈不对称的耗尽区，所制造的 Se/Si 器件在红外区域之前保持了与硒器件类似的波长截止，并且在紫外到可见光区域中具有高性能宽带光响应。大面积光电探测器在-2 V偏压下保持极低的漏电流，并在500 nm处获得62 nA的高光电流，获得10(3)-10(4)的高开/关比。当去除偏置电压时，可以清楚地观察到光响应。脉冲响应精确地提供了高响应速度（tau（上升）+ tau（下降）大约为 1.975 毫秒），超过了当前报告中最快的硒基光电探测器。增强的光电性能和自功率光响应主要来源于同时具有晶格匹配和II型能带匹配的集成高质量Se/n-Si p-n异质结。
A gold-induced NH4Cl-assisted vapor-based route is proposed and developed to achieve vertically aligned submicron Se crystals on lattice-matched (111)-oriented silicon substrates, based on which a high-performance large-area silicon-compatible photodetector is constructed. Thanks to the energy band structure and the strongly asymmetrical depletion region, the fabricated Se/Si device maintains a similar wavelength cutoff to that of selenium devices before the IR region, along with a high-performance broadband photoresponse in the UV-to-visible region. The large-area photodetector maintains a very low leakage current under a -2 V bias, and a high on/off ratio of 10(3)-10(4) is obtained with a high photocurrent of 62 nA at 500 nm. A photoresponse is clearly observed when the bias voltage is removed. The pulse response precisely provides a high response speed (tau(rise) + tau(fall) approximate to 1.975 ms), exceeding the fastest Se-based photodetectors in current reports. The enhanced photoelectric properties and the self-power photoresponse mainly derive from the integrated high-quality Se/n-Si p-n heterojunctions with both lattice match and type II energy band match.