Abstract Photodetectors with molecular beam epitaxial CdTe single-crystalline films on SrTiO3 were fabricated by varying the channel length to optimize the response performance. Optoelectric properties were characterized by semiconductor characterization system and high-speed oscilloscope. Crucial detecting parameters were extracted and their dependences on channel length were summarized. The responsivity, detectivity and gain increased exponentially with contracting the channel length while the response time and photo-to-dark current ratio exhibited a linear dependence. Ultrafast response speed with the ultrashort response time of ≈1.7 ms and high on/off ratio of ≈7.3 were achieved in the 3 μm channel size photodetector. Pole figure of CdTe/SrTiO3 epitaxial system was performed to explain the low response properties and the trade-off among these response parameters was also discussed.

中文翻译：

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在钙钛矿 SrTiO3 上具有 MBE CdTe 单晶薄膜的光电探测器中光电性能对沟道长度的依赖性

摘要 通过改变沟道长度以优化响应性能，制备了在 SrTiO3 上具有分子束外延 CdTe 单晶薄膜的光电探测器。光电特性通过半导体表征系统和高速示波器进行表征。提取了关键检测参数并总结了它们对通道长度的依赖性。随着通道长度的缩短，响应度、探测度和增益呈指数增长，而响应时间和光暗电流比则呈现线性相关性。在 3 μm 通道尺寸光电探测器中实现了超快响应速度和 ≈1.7 ms 的超短响应时间和 ≈7.3 的高开/关比。