Summary: | 碩士 === 國立中山大學 === 電機工程學系研究所 === 95 === Recently, wirebonding process play an important role in IC assembly packaging manufacture. No degradation of bonding wire interconnection and defect free eutectic alloy bonding offer the high yield and reliability of products.
The degradation of Au wire/Al bond pad has become a major bonding failure problem. By utilizing the SEM, AES, EDS and XPS techniques, it could be carried out to reveal and identify defects underneath Al layer, and the contaminated Al bond pads could cause poor intermetallic growths led to the failed or unreliable connections from the chip to the outside world. It is because that the molding resin with low thermal stability (e.g. bi-phenyl epoxy resin) and the IC devices under high thermal environments were used in packaging process. For the lifetime to bond failure, the bi-phenyl epoxy molding becomes shorter than that for cresol novolac epoxy due to the corrosion reaction of Au-Al intermetallics with bromine (Br) contained in the resin compounds. It was clarified that the reactive intermetallic was Au4Al phase formed in the bond interface.
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