Effects of wire type and mold compound on wearout reliability of semiconductor flash fineline BGA package

This paper discusses the influence of wire type (Cu and Au) and the effect of mold compound on package reliability after exposure to component reliability stress tests. Failure analysis is conducted to identify associated failure mechanisms, and wearout reliability of both wire types investigated after biased HAST (HAST) and Temperature Cycling (TC). Weibull plots are plotted for each reliability stress. Cu (Copper) ball bonds are found to have better reliability margin in biased HAST stress compared to Au (Gold) ball bonds for both mold compounds. Cu wire also exhibits a better reliability margin compared to Au ball bonds in the TC stress test. Failure mechanisms of HAST and TC are proposed for both wire alloys in this paper.