BGA锡球再置可靠性(英文)

BGA Reballing Reliability

已有很多关于混合合金焊点的可靠性的文章发表,主要重点放在BGA器件上。乍看起来,这些BGA器件上的混合合金焊点看来有可以接受的焊点强度及可靠性,但工序要求对回流焊工艺和温度曲线有更大的控制。因此,很多制造商以含铅锡球工艺对无铅BGA进行锡球再置,并未更改工序即加工组件。论述了有关经再置锡球的器件的可靠性问题,特别是器件焊盘铜溶解及额外热循环对芯片/封装的影响。

A study of multiple reball processes looks at cop- per dissolution and functionality. There are many differences in the alignment and placement of balls for reattachment. Yet to ensure a good metallurgical and mechanical attachment, the common element for all reballing methods is the need to reflow solder balls while aligned on the BGA lands. Most questions concerning BGA reballing pro- cess reliability focus on two specific areas： First, the physical or mechanical strength and reliability of the ball attach to the device.