Reliability analysis of 3D CSP MEMS and IC under thermal cycle-impact coupled multi-physics loads

In this paper, reliability analysis of 3D CSP MEMS and IC under thermal cycle-impact coupled multi-physics loads was investigated. COMSOL Multiphysics, a finite element software, was used to analyze the mechanical behavior of our device under a -55°C/125°C thermal cycling and 1500G@1ms with half-sine pulse impact coupled load. MEMS chip was bonded on a silicon interposer by solder balls. An application specific integrated circuit (ASIC) for the signal processing was placed on the interposer beneath the MEMS. Combining the effects of thermal stress and impact loads, we hope to find out the failure modes of interconnect structures including solder joints and whole device. The deformation and stress distribution of the overall device will be carried out for layout optimization of interconnect structures.