【摘要】 陶瓷覆铜基板在大功率电力电子器件封装模块中有着重要的应用,作为传统模块电气互连的重要组成部分,其通过超声键合技术将键合引线与其相连实现电气互连,因此,陶瓷覆铜基板的可键合性直接决定了模块生产的可靠性和成品率。以前的研究主要集中在键合参数(键合功率、键合压力、键合时间)对键合性能的影响,本文则从陶瓷覆铜基板表面形貌几何形态的角度出发,研究了其对陶瓷覆铜基板与粗铝线超声可键合性的影响。通过实验分析发现,基板表面形貌的几何特性对可键合性能有着重要的影响,一方面,表面轮廓的微观不平度的平均间距Sm(空间频率特性)影响超声可键合性。平均间距Sm越小,表面纹理越细密,其可键合区域大,键合成功率较高;反之,Sm参数太大,则会削弱基板的可键合性。另一方面,表面粗糙度Ra影响键合强度的稳定性,在键合成功的前提下,表面粗糙度越小,其键合强度的离散性越小。并利用频谱分析方法及摩擦学的理论对产生这种现象的原因进行了理论分析解释。更多还原

【Abstract】 DBC(direct bonding copper) plate, as an important part to fulfill electrical connection by using ultrasonic bonding technique in classical power module, has a wide application in high power electronic device module. As a result, the bondability of DBC plate has a vital influence on products’ rate and reliability. Previous studies focused on how the bonding parameters(power bonding, pressure bonding, bonding time) affect the performance of the bonding. However, few researches of surface morphology on the wire bondability were reported. This paper presents a study of the surface morphology of DBC plate on the ultrasonic wire bondability. The results of experiments show that the average distance between the microscopic irregularities(Sm) of the surface morphology of DBC plate has a very important influence on bondability. On one hand, better bondability will be abtained if the parameter Sm of the DBC plate surface is smaller. Otherwise, the bondability of DBC plate will be much worse. On the other hand, the bonding strength discreteness is decided by the surface roughness based on thesuccessful bonded, the smaller of the surface roughness is, the less discrete of the bonding strength is. Lastly, these results are analysed by using spatial spectrum method and tribology theory.更多还原