The Damage Threshold Of Detector By Laser Irradiation

The PIN detectors will be damaged even can not work normally when the PIN detectors are irradiated by laser of different power density. The topic of irradiation on PIN detectors by laser of different power density was researched systematically. First, the interaction between laser and semiconductor and the measuring method of damage threshold were introduced simply. Then, the damage threshold of the PIN detectors was measured by energy method of scattered light, and the light distribution of the scattered light as well as the surface topography of the crystals were observed and the damage threshold of 4.1×108W/cm2 was obtained with the reflectivity falling down about 11% and comparatively severe ablation and large cracks appearing on the surface of crystals. In the end, the simulation about the process of irradiation on Si crystals by laser was done using finite-element software ANSYS and the results of the calculation were bigger than the experimental results. The main reason was that the impurity and the shortage of the Si crystals made the damage threshold of the detector reduced.