Technique to predict reliability failure in side-gate transfer molded packages

Abstract

Scanning acoustic microscopy (SAM) is the primary method to non-destructively detect internal defects in finished semiconductor packages. SAM is heavily used to detect interfacial delamination in the die-package system. Though this method can achieve an acceptable resolution to analyze the quality of the package unit, it is not absolute in all cases. SAM is also time consuming and non-predictable, as it offers a latent response of the finished good to the reliability tests. This paper presents an analytical prediction method defined to gauge whether the epoxy mold compound (EMC) encapsulating a no polyimide (PI) die surface would yield detectable delamination at the die to mold compound interface in the package finished good. The new method can be used to gauge whether top of die to EMC delamination will occur with a change in new wire bond (WB) die layout, new EMC material and new mold process. This new method also provides a way to demonstrate that the observed delamination is not detrimental to package reliability. This method will demonstrate how the no-PI package reliability can be met to not cause electrical failures based on the resin rich (RR) volume.