BSOB键合互连在厚膜混合电路中的应用研究

Application Research on BSOB Wire Bonding Interconnection of Thick Film Hybrid Circuit

在厚膜混合IC的基板键合区中,存在玻璃相残留、平整性差、沾污等问题。采用常规安全成球(BBOS)工艺进行芯片与基板互联时,存在键合不粘、短线尾等异常问题。本研究采用先植球后打线(BSOB)键合工艺,消除了键合过程中的异常问题。对比了BSOB、BBOS两种方式的可靠性,研究了劈刀磨损对BSOB方式的可靠性影响。结果表明,BSOB方式在初始拉力和300℃/24 h后的拉力及过程能力指数(Cpk)均明显高于规范值,键合40万个点后,无明显变化。BSOB方式是一个键在另一个键上面形成的复合键合,满足GJB548规范要求。

Due to the glass frit remained on the uneven bonding surfaces of the thick film hybrid integrated circuits(HIC)substrate,together with the contamination introduced during the assembly of the HIC,non-sticking on the substrate and short tail frequently occurred,when conventional BBOS wire bonding technique was used for the interconnections of the dies and substrate.In this paper,BSOB bonding technique was used to eliminate the bonding process problems.The reliability of the BSOB and BBOS was compared.Also the abrasion of the capillary on the effect of the bonding reliability was studied.The results indicated that both the wire pull and the process capability index(Cpk),of the initial and after 300℃/24 h,were obviously higher than the specified values,and showing no evident variations after 400000 bonds.BSOB technique was compliant with the GJB548 for a compound bond,where one bond was placed on top of another bond.