钎料球激光重熔温度场数值模拟

对PBGA封装制造时钎料球的激光重熔过程中的温度场分布进行了数值模拟，考察了多点和扫描两种激光加热方式对温度场的影响，计算结果表明，与红外、热风等传统重熔方法相比，激光重溶具有加热时间短、封装内部温升低的特点，不会对内部芯片及连接造成损害，同时，本文还对PBGA钎料球激光重熔进行了试验研究。试验结果表明，在合适的规范下，重熔后形成的钎料凸点表面质量也优于前者。

Numerical Simulation on Temperature Distribution of PBGA Package during Laser Reflow Process

In this paper,temperature distribution of PBGA component during laser reflow process of solder ball was simulated with finite element method,and effects of different heating means of laser on temperature distribution were discussed in detail.Results of simulation showed that reflowing solder balls with laser can not damage the silicon chip and package with the characters of short heating time and low temperature in package comparing with traditional heating method such as infrared reflow and hot air reflow method.At the same time,experiments on PBGA solder ball laser reflow were carried out.Results of experiment showed that surface of solder bump achieved by laser reflow method with proper parameters is much smoother than that achieved by hot air reflow method.