关键词: 引线键合, 金属间化合物, 焊盘加固, 凸块, 可靠性

Abstract: Cu/Ni/Au bump was prepared on the surface of the Al pad of the chip to strengthen the pad, and the optimization of the pad structure solved the problems of narrow process window and long-term reliability of gold-aluminum bonding during gold wire bonding for conventional chip aluminum pads. After the chip was strengthened, the strength was effectively avoiding the short circuit problem caused by breakdown of the dielectric layer under the pad during bonding. The presence of the Ni layer effectively avoided the Kirkendall void problem caused by the growth of intermetallic compounds during high-temperature storage. Experiments confirmed that pad reinforcement can greatly improve the process window of wire bonding, and the interface organization after pad reinforcement remained highly stable in a high-temperature storage test at 300 ℃ and 24 h.

Key words: wire bonding, intermetallic compound, strengthening die pad, bump, reliability