InSb红外焦平面列阵探测器局部分层失效机理研究

批量生产中，锑化铟红外焦平面列阵探测器(InSb IRFPAs)局部分层失效现象已成为制约其成品率提升的瓶颈。为探究InSb IRFPAs局部分层诱因，借助内聚力模型，在InSb芯片与底充胶的界面处铺满内聚力单元，优选内聚力模型参数，建立InSb IRFPAs局部失效分析二维模型。模拟结果得到了实测局部分层分布特征的证实，即:(1) 局部分层大多出现在芯片周边区域，涵盖一定宽度；(2) InSb芯片与底充胶之间的界面局部脱开后，逐渐向两侧扩展。为剖析局部分层诱因，系统分析了张开型与滑开型裂纹扩展共同作用下混合模态比取不同值时局部分层分布特征的演化规律，认为当张开型和滑开型裂纹扩展的混合比取4: 6时，模拟结果与实测结果高度吻合。至此笔者认为InSb IRFPAs局部分层源于界面法向应力与面内剪切应力的共同作用，属于典型的混合型局部分层模式，其中滑开型局部分层模式占主导。

Research on local delamination failure mechanism of InSb infrared focal plane arrays detector

Local delamination failure phenomena of indium antimonide infrared focal plane detectors (InSb IRFPAs) in their mass production have become a bottleneck restricting the improvement of their final yield. In order to determine the inducement of local delamination in InSb IRFPAs, the interface between the InSb chip and the underlying underfill with cohesion units was covered, and the specified parameters in cohesion model were optimized, finally the two-dimensional model of local delamination failure analysis of InSb IRFPAs was established. Simulation results are verified by the measured distribution characteristics of local delaminations, that is, (1) Most local delamination appears in the surrounding edges of InSb chip, and occupies a certain width; (2) Once the InSb chip is separated from the underlying underfill in the normal direction, the local delamination will expand gradually toward its both sides of the plane. In order to clarify the inducement of the local delamination, the evolution rule of the local delamination with different mixed-mode ratios is systematically analyzed under the jointed action of both the opening mode and sliding mode. The simulation results are highly consistent with the measured results when the mixed-mode ratio between the opening mode and the sliding mode is set to 4: 6. The local delamination of the InSb IRFPAs are ascribed to the jointed action of both the interfacial normal stress and the in-plane shear stress, is the typical mixed-mode local delamination mode, furthermore, the sliding local delamination mode is dominant.