K. Kamthongsuk, P. Kongsubto, S. Kongwudthiti, R. Lochingchairit, P. Kongjaroon, Y. Yousoom, Spansion (Thailand) Ltd., Nonthaburi, Thailand

Summary: The novel sample preparation method using the combination of sequential mechanical treatments (grinding), and chemical treatments (Potassium Hydroxide- KOH & Dilute Hydrochloric Acid- HF) provides more robust, more accurate and easier to handling with for determining the percentage of inter-metallic formation area formed on the bonding pads of both BGA and lead IC packages structures. Series of experiments with statistical analysis had been conducted to confirm the results.