In this paper, we reported the fabrication of improved CH3NH3PbI3/Si heterojunction photodetectors (PDs) achieved by passivating the interfacial defects by a low-temperature atomic layer deposition-grown thin amorphous HfO2 layer. The results suggested that the HfO2 thin layer effectively passivated the surface defects of Si and slightly improved the qualities of CH3NH3PbI3 thin films in terms of increasing the grain sizes. Current–voltage measurements suggested that the HfO2 thin layer suppressed interfacial Shockley–Read–Hall recombination, which decreased the dark current and simultaneously increased the photocurrent. However, a thick HfO2 layer resulted in a decrease in the photocurrent because of the insulting nature of HfO2. A champion performance was obtained by employing a 5 nm HfO2 layer, where the responsivity and detectivity were 0.6 mA/W and 8.0 × 1010 Jones, respectively, which are two times and four times as high as those PDs without the HfO2 layer. The results will provide a simple strategy for improving the performance of perovskite/Si heterojunction PDs in the future.

中文翻译：

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通过使用非晶氧化铪薄层对改进的 CH3NH3PbI3/Si 异质结光电探测器进行界面钝化


在本文中，我们报道了通过低温原子层沉积生长的薄非晶态 HfO2 层钝化界面缺陷而制备改进的 CH3NH3PbI3/Si 异质结光电探测器 （PDs）。结果表明，HfO2 薄层有效地钝化了 Si 的表面缺陷，并在增加晶粒尺寸方面略微改善了 CH3NH3PbI3 薄膜的质量。电流-电压测量表明，HfO2 薄层抑制了界面 Shockley-Read-Hall 复合，这降低了暗电流，同时增加了光电流。然而，由于 HfO2 的绝缘性质，厚的 HfO2 层导致光电流降低。采用 5 nm HfO2 层获得冠军性能，其中响应度和检测率分别为 0.6 mA/W 和 8.0 × 1010 Jones，分别是没有 HfO2 层的 PD 的两倍和四倍。结果将为未来提高钙钛矿/硅异质结 PD 的性能提供一种简单的策略。