Local Cleavage of indium antimonide (InSb) chip always occurs in the mass production of the InSb infrared focal plane detectors (IRFPAs), this specific fracture phenomenon restricts the improvement of the yield of the InSb IRFPAs. After analysis, we think that the cleavage of InSb chip at the edge region of the InSb IRFPAs is related to the splashed gold bump existing in this region, this failure phenomenon dominates with the low-cyclic liquid nitrogen shocking tests. In order to clarify the influence of the splashed gold bump on the cleavage of the InSb chip, we established a structural model of the InSb IRFPAs containing the splashed gold bump, and analyzed the influence of the splashed gold bump on the thermal stress distribution in the InSb chip. Besides, we preset the initial cracks with different lengths at the stress concentrations sites to describe the dislocations in InSb wafers, basing on the energy release rate, we obtained the relationship between the cleavage of the InSb chip and the dislocation line length with the existed splashed gold bump. The main conclusions are as follows: 1) The influence of the splashed gold bump on the cleavage of the InSb chip is local, and two stress concentration sites are formed on the outermost part of the contact region between the splashed gold bump and the InSb chip; 2) The energy release rate surrounding the preset crack increases ly with the increased preset crack length; 3) Cleavage of the InSb chip caused by the splashed gold bump belongs to the type I fracture failure mode. In the cyclic liquid nitrogen shocking tests, the dislocation line gradually punches through the InSb chip under the driving of the concentrating stress, and forms the macro cleavage of the InSb chip.
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