Verification of Numerical Models Used in Microelectronics Packaging Design by Interferometric Displacement Measurement Methods

Abstract

Verified/predictive modeling has become an integral part of electronic packaging product development in order to reduce costs and cycle time. In this paper, interferometric displacement measurement methods are utilized to verify the validity of numerical models for microelectronics packaging design. Three optical methods with submicron sensitivities are employed: moiré interferometry, microscopic moiré interferometry and Twyman/Green interferometry. The first two provide contour maps of in-plane displacement fields, and the third maps out-of-plane displacement fields. Their high sensitivity and high spatial resolution make them ideally suited for verification of numerical models. By combining numerical modeling and experimental verification until the results merge, numerical models become more accurate and dependable. Then, the models can be applied extensively to optimize the package designs with confidence that the models provide effective information on material and geometry sensitivity.