Thermal Deformation Measurement by Digital Image Correlation Method

Thermal-mechanical behavior of materials and reliability assessment of semiconductor packages are two of key issues in electronic packaging. Digital image correlation method is increasingly used for thermal deformation characterization in electronic packaging in recent years. For example, the deformation measurements of solder joints in various semiconductor packages have been reported in previous studies. However, the noise effects on measurement accuracy under thermal loading conditions have been less evaluated. When acquiring images of a specimen subjected to thermal loading in a chamber with glass window, the influences of the computer vision system, specimen surface condition, out-of-plane deformation and rigid body translation and rotation are required to be addressed. In this paper, such critical factors are evaluated during the calibration of a digital image correlation system. Proper measures are introduced to minimize the noise level. The thermal deformation measurement of a solder joint in a BGA (ball grid array) package is also demonstrated