Abstract This study is focusing on dark current and 1/f noise characteristics of In0.74Ga0.26As photodiode passivated with different passivation films. With regard to mesa-type wavelength-extended InGaAs photodiode, surface passivation process plays an important role in reducing the excess leakage current of the device. With the development of passivation process, atomic layer deposition (ALD) has been used in the fabrication process of photodetectors. In order to reduce the side current of In0.74Ga0.26As photodiodes, SiNx film and SiNx/Al2O3 bilayer have been considered as the passivation film, respectively. The dark current test results indicate that SiNx/Al2O3 bilayer can effectively reduce side current of In0.74Ga0.26As photodiodes compared to SiNx film. Moreover, the results of noise frequency spectra qualitatively demonstrate that SiNx/Al2O3 bilayer can significantly decrease the interface states density, thereby reducing the 1/f noise of photodiodes.

中文翻译：

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SiNx/Al2O3双层钝化In0.74Ga0.26As光电二极管的暗电流和1/f噪声特性

摘要 本研究重点研究不同钝化膜钝化的In0.74Ga0.26As光电二极管的暗电流和1/f噪声特性。对于台面型波长扩展 InGaAs 光电二极管，表面钝化工艺对降低器件的过大漏电流起着重要作用。随着钝化工艺的发展，原子层沉积（ALD）已被用于光电探测器的制造过程中。为了降低 In0.74Ga0.26As 光电二极管的侧电流，分别考虑使用 SiNx 膜和 SiNx/Al2O3 双层作为钝化膜。暗电流测试结果表明，与SiNx薄膜相比，SiNx/Al2O3双层可以有效降低In0.74Ga0.26As光电二极管的侧电流。而且，