Thermo-mechanical behaviors of electronic packaging materials and structures by high temperature Moire interferometry

摘要

In this study, moire interferometry method was applied in the thermo-mechanical analysis of microelectronic packages, with both high temperature grating replication and real time measurement techniques. The grating replication technique of moireinterferometry at the temperature up to 200°C was presented for the coefficient of thermal expansion (CTE) measurement of metal ball grid array (BGA) package. Considering the complicated and large thermal deformation of electronic packages, gratings of600 l/mm was used instead of traditional gratings of 1200 l/mm in the thermal displacement measurement of the flip-chip (BGA) package cross-section. Thermal deformation of the packaging systems was measured and the effects of the encapsulation, soldering, and geometry on the deformation were investigated. The real time measurement of moire interferometry was also applied with the aid of a vacuum thermal chamber and a computer imaging analysis system. Thermal deformation of electronic package as a functionof temperature was analyzed. CTE of packaging materials molding compound was measured from room temperature to 260°C.