功率器件粗铝丝键合脱键失效机理分析  

Disbonding Failure Mechanism Analysis of Heavy Aluminum Wire Bonding for Power Devices

作　　者：路聪阁[1] 鲍禹希 李彩然 刘彤 张国良 宋云鹤 任宇欣 Lu Congge;Bao Yuxi;Li Cairan;Liu Tong;Zhang Guoliang;Song Yunhe;Ren Yuxin(The 3th research institute of CETC,Shijiazhuang 050000,China)

机构地区：[1]中国电子科技集团公司第十三研究所,河北石家庄050000

出　　处：《广东化工》2022年第13期87-89,83,共4页Guangdong Chemical Industry

摘　　要：粗铝丝键合具备过流大、键合灵活的优点,被广泛应用于VDMOS等大功率器件的封装。但功率器件工作时发热量大,粗铝丝/金层键合系统在长时间高温的环境下,容易发生引线剥离脱落,导致器件失效。本文利用SEM/EDS以及FIB等测试手段,系统研究了Al/Au界面的金属间化合物(intermetallic compound,IMC)及柯肯达尔空洞(kirkendall hole)的形成对粗铝丝键合脱键失效的影响。结果表明:粗铝丝键合脱键是源于高温过程中,金铝之间形成多种金属间化合物,引起体积变化,形成了连续的柯肯达尔空洞,最终导致键合脱键失效;降低金层厚度可以有效降低粗铝丝脱键导致的失效风险。Heavy aluminum wire bonding has the advantages of large current and bonding flexibility,and is widely used in the packaging of high-power devices like VDMOS.The power device generates a large amount of heat when working,and the heavy aluminum wire bonding system is prone to lead stripping and falling off in a long-term high temperature environment,resulting in device failure.The effects of intermetallic compounds(IMC) at the gold-aluminum interface and the formation of Kirkendall holes on the disbonding failure of heavy aluminum wire bonding were systematically studied.The results show that the disbonding of the heavy aluminum wires is due to the formation of various IMCs between gold and aluminum during the high temperature process,resulting in volume changes and the formation of continuous kirkendall holes.Reducing the thickness of the gold layer can effectively minimise the risk of failure caused by heavy aluminum wire disbonding.

关 键 词：铝丝键合 金属间化合物(IMC) 柯肯达尔空洞 脱键 功率器件 

分 类 号：TN305[电子电信—物理电子学]