激光辐照光伏型光电探测器热效应的有限元分析

建立了高斯激光辐照光伏(PV)型光电探测器温升的三维物理模型，采用有限元分析方法计算了探测器的三维温度场分布，探讨了辐照时间、胶层厚度和胶层热导率对熔融损伤阈值及热恢复时间的影响。研究结果表明：InSb PV型探测器受到强激光连续辐照时会发生熔融损伤破坏，且最早发生于迎光面的光斑中心；激光的功率越高，造成损伤破坏所需要的时间越短；热导率越大，越薄的胶层对应的损伤阈值越大，但胶层厚度和热导率对熔融损伤阈值的影响在大功率激光辐照时才较明显。为了提高PV型探测器抗激光辐照能力，应选用热导率大且尽可能薄的胶层。采用该模型计算得到10W功率激光辐照下的熔融时间为3.26s,与实验得到的3s基本吻合。

Finite element analysis of thermal effect of photovoltaic detector irradiated by laser

A 3-D physical model of temperature rise for a photovoltaic detector irradiated by Gaussian CW laser is established. The 3-D temperature distribution of the detector is calculated with finite element analysis method. The effects of the irradiation time, the thickness and heat conductivity of glue layer on the melting damage threshold and heat recovery time are discussed. The research results show that the melting damage may occur in the InSb photovoltaic detector when it is radiated continuously by intense laser, and the damage takes place first in the light spot center of the radiated surface. The higher the laser power is, the shorter time the damage takes, and the greater the heat conductivity is, the bigger the damage threshold corresponding to the thinnest glue layer will be. However, only when the detector is radiated by the high power laser, will the effect of the thickness and heat conductivity of the glue layer on the melting damage threshold become clear. The results obtained from the research match well with the experiments. It is pointed out that the glue with high heat conductivity should be selected and the thickness of the glue layer should be made as thin as possible to improve the performance of the photovoltaic detector.