Stress measurement and simulation of the key silicon-based structures based on infrared photoelasticity

Abstract

It is important to evaluate the reliability of the key silicon-based structures such as Through silicon vias (TSV) and Micro-electromechanical Systems (MEMS). The thermo-mechanical stress of TSV and the bonding stress of MEMS are quantitatively determined in this paper based on real-time phase shifting using a polarization camera. The polarizated images based on finite element simulation are reconstructed by stress-optic law and Mueller matrix multiplication for experimental verification. A economical infrared polariscope without rotation of optical elements is developed to provide a rapid measurement of stress in silicon-based structures. The error correction algorithm for the low extinction ratio in infrared polariscope is used for measurement of stress. Experimental results indicate that the infrared photoelastic system enables measurement of stress in TSV and MEMS.