大质量中间无引脚PGA器件加固及解焊技术

Reinforcement and Rework Technology of Large Weight and Middle Area Pin-Free PGA Packaging Devices

为确保大质量中间区域无引脚的PGA封装器件在航天领域的可靠应用,提出了一种新的加固方法,并进行了严苛力学+热循环的可靠性试验,试验后对焊点进行了金相分析。分析结果表明,大质量中间区域无引脚PGA封装器件采用底部填充环氧胶、四角+四边点封环氧胶的方式,经过可靠性试验后,焊点外观及内部未见裂纹产生。加固方法能够满足严苛力学条件下的使用要求。通过优化器件解焊工艺方法,为器件的拆除和更换提供了解决方法。

In order to ensure the reliable application of PGA packaging devices with large weight and middle area pin-free in the aerospace field,a new reinforcement method is put forward,and the reliability test of rigorous mechanical and thermal cycle is carried out.The metallographic analysis of solder joints was carried out after the test.The analysis results show that,no cracks are found in the appearance and interior of solder joints when the large weight middle area pin-free PGA packaging devices are filled with epoxy at the bottom and sealed with epoxy at four corners and four edges after reliability test.The reinforcement method can meet the requirements under the rigorous mechanical conditions.By optimizing the rework process,a solution is provided for the dismantling and replacement of the devices.