Influence of Structure Parameters on Performance of Silicon PIN Photodetector

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.