基于激光加热的引线键合方法及其试验研究

Method and Experimental Research of Wire Bonding Based on Laser Heating

温度对引线键合的质量有着重要的影响,为了解决MEMS芯片混合封装中不能整体加热的局限性,自主设计了一种激光照射下的金丝引线键合系统并针对其适用面做了试验研究。通过研究不同材料对激光的吸收效果,利用ANSYS有限元分析软件对激光作用下的焊盘温度进行仿真,仿真结果表明:激光热效应明显,仅需1 s就可以将焊盘加热到所需温度,并且激光在不同材料下热效应差异较大。将激光加热工艺加入到基于机器视觉作用下的引线键合系统,操作简单灵活、精准度高,可以针对不同材料焊盘实时调整激光功率以满足键合温度需要;因此,该引线键合方法可广泛应用于需要局部加热的MEMS芯片引线互连中。

Temperature has important effect on the quality of wire bonding. In order to solve the limitation of hybrid packaging of MEMS chip without whole heating,design a new gold wire bonding system under laser heating and conducted a series of experiments specifically. By studying the laser absorption effect of different materials,using ANSYS finite element analysis software to conduct temperature simulation on laser heating bonding pad. It shows that laser thermal effect is obvious and bonding pad can be heated to the required temperature only in 1 s. Meanwhile the laser heating effects are different under the different materials. This laser heating technique was added to wire bonding system based on machine vision and it has advantages of simple operation and high accuracy. Can adjust the laser power to satisfy the bonding temperature with different material bonding pad. Therefore,this wire bonding method can be widely used for MEMS chip connection which required partial heating.