硅基PIN光电探测器结构参数对其性能的影响

Influence of Structure Parameters on Performance of Silicon PIN Photodetector

对硅基PIN光电探测器器件模型进行了理论分析,讨论了硅基PIN光电探测器的I-V特性与器件的i层厚度和整体宽度的变化关系,并进行了仿真分析。实验结果表明,随着i层厚度从5μm增加到70μm,器件的正向电流逐步减小,且i层厚度与其正向电流成反比;随着器件宽度从50μm增加到90μm,器件的正向电流逐步增大,且器件宽度与其正向电流成正比;引入保护环结构可以明显降低器件的暗电流。对PIN器件的结构参数进行了优化设计,结果表明在所设置的器件工艺条件下,当器件的i层厚度为50μm、整体宽度为70μm时,器件的性能最佳。

The performance of silicon PIN photodetector highly depends on the chip geometry and the semiconductor material,especially in the intrinsic region.Based on making theory analysis on the model of silicon PIN diode,the effects of width and thickness variations of the intrinsic region of silicon PIN diode on its I-V performance was discussed and simulated using Silvaco TCAD tools.The simulation results show,the forward current decreases with the increasing thickness of the intrinsic region from 5 μm to 70 μm,but it increases with the increasing width of the device from 50 μm to 90 μm.And it is proved that the guard ring can significantly reduce the dark current.The best performance of the device is obtained with the thickness of the intrinsic layer of 50 μm and the overall width of 70 μm.