高斯激光辐照焦平面探测器温度场分析与仿真

为了研究激光辐照焦平面探测器的温度效应,采用ANSYS有限元软件建立高斯脉冲激光辐照锑化铟红外焦平面探测器的3维结构分析模型,并对该探测器3维温度场效应进行了研究。结果表明,激光辐照下,探测器最大温度出现在最上层的锑化铟芯片上,探测器最大温度达到锑化铟芯片熔点温度798K时,将会引起探测器的热熔融损伤,且熔融损伤阈值受到脉宽、光斑半径等激光参量的影响;高斯脉冲激光辐照下,探测器中各层材料的温度场分布呈现出非连续的高温极值区域,其主要原因是位于锑化铟红外焦平面探测器中间层相间分布的铟柱和底充胶具有迥异的热学性质,并且造成探测器温度场云图中锑化铟芯片、底充胶与硅读出电路高温极值区域形成类似于互补的高温分布。这为进一步研究温升效应引起的应力场分布、提高探测器激光防护性能提供了重要的理论分析依据。

Analysis and simulation of temperature field of focal plane array detector irradiated by Gaussian laser

In order to study laser irradiation temperature effect of a focal plane array detector under laser irradiation, 3-D analysis model of InSb infrared focal plane array detectors with complex multilayer structure was established based on ANSYS software, and 3-D temperature field and temperature effect of InSb infrared focal plane array induced by Gaussian pulse laser was simulated. The simulation results show that, the maximum temperature occurs in InSb chip, locating at the uppermost layer of the InSb detector. When the maximum temperature of InSb chip reaches the melting temperature 798K of InSb material, hot melting damage for the detector would happen and the melting damage threshold was also influenced by the laser pulse wide width and spot radius of laser. Temperature field distribution of each layer material in InSb detector shows non-consecutive high temperature extreme areas. The main reason is that, Indium bump and underfill, which are the alternative distribution in the middle layers of InSb focal plane array detectors, have different thermal properties. And then, extreme heat region of InSb chip, underfill and silicon readout circuit has high-temperature distribution similar to complementary in cloud map of detector temperature field. The research is useful for studying stress field distribution caused by temperature effect and improving laser protective performance of detector.