红外焦平面探测器中间层杨氏模量提取研究

Young's modulus calculation of the interlayer in infrared focal plane array detector

为系统研究热冲击下InSb焦平面探测器的形变规律,需借助多层材料形变分析方程组求得其形变解析解。本文在分析、模拟双组份弹性材料均匀混合后其等效杨氏模量随体积分数变化趋势的基础上,借助有限元软件ANSYS对InSb焦平面探测器中间层等效杨氏模量的提取进行系统研究。分析结果表明,直接采用线弹性材料模型模拟的结果与真实材料的等效杨氏模量相去甚远,需用黏塑性模型方能给出符合实际的中间层等效杨氏模量;在InSb焦平面探测器典型结构设计中,中间层的等效杨氏模量随体积分数的演化规律可用线性方程描述,这为后续探测器结构优化提供了理论分析模型支撑。

In order to explore the deformation rules of InSb infrared focal plane array detector under the thermal shock, We need solve the equation set describing the deformation of a multi-layer material system. In the equation set, the equivalent Young’s modulus of the interlayer in the InSb infrared focal plane array detector is unknown. So in this paper, We firstly analyze the changing tendency of the equivalent Young＇s modulus of the interlayer mixed uniformly by two elastic materials, which is determined by the material volume fraction. Secondly, employing the finite element method, we calculate the equivalent young＇s modulus of the interlayer in InSb infrared focal plane array detector. Analysis results show that the equivalent young＇s modulus calculated directly by two linear elastic material models is larger than its real value, and the viscoplacticity model, describing the stress-strain character of the indium bump array, should be employed to acquire its real value. Finally, we draw a conclusion that in the interlayer of the InSb infrared focal plane array detector, the relationship between its equivalent young＇s modulus and the indium volume fraction can be described with a linear equation. This finding provides a theoretical analysis model to optimize the structure of InSb infrared focal plane array detector in the following study.