Hi Michael:
這種特殊封裝, 理論上應該是MCM(multi chip module), 多顆芯片非對稱擺放可能造
成warpage, 進而對錫球產生應力. 一般封裝大廠會進行shadow morrie與MSL驗證, 
或Board Level上板驗證應可篩選出warpage或CTE mismatch等問題. 亦或在EMS端加
上Underfill來減少在錫球上的應力, 但會增加費用/工序與返工問題.
建議您先從異常品上確認問題, 再研議後續分析規劃.

Yenchi / 陳彥奇
iST-Kunshan (昆山宜特科技)
Engineering Director
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iST Group(宜特/宜碩)
FIB / FA / Reliability / MA / Chemical(RoHS/REACH) Laboratory
Lab. Location : Shanghai, Kunshan, Beijing, Shenzhen, Taiwan
US : Sunnyvale
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Chen Hao <[log in to unmask]> 
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2013-12-25 14:12
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[TGAsia] IC 焊接问题






Hi All
 
请问同行这样封装的IC，Reflow条件及生产过程中是否有特别需要注意的点？
另外，这种封装的IC四个角落是否特别容易出现Crack现象？该如何避免及预防？
 
以上，谢谢！

 
BR,
Michael
 

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