首页 | 本学科首页   官方微博 | 高级检索  
     检索      

温度循环条件下镀锡引脚的晶须生长
引用本文:张金松,吴懿平,朱宇春,李娟娟,吴丰顺,安兵.温度循环条件下镀锡引脚的晶须生长[J].上海交通大学学报,2007(Z2).
作者姓名:张金松  吴懿平  朱宇春  李娟娟  吴丰顺  安兵
作者单位:华中科技大学材料成形与模具技术国家重点实验室,武汉光电国家实验室 湖北430074,湖北430074
基金项目:国家自然科学基金资助项目(10474024),湖北省自然科学基金资助项目(2006ABA091)
摘    要:在热循环条件下,对电镀纯Sn覆层的器件引脚的锡须生长进行了评估.当器件经历500与1 000次温度循环后,纯Sn镀层表面会产生致密的热疲劳裂纹,伴随生长出许多锡须.由于镀层表面的SnO2氧化膜与镀层中Sn的热膨胀系数(CTE)存在较大的差异,在温度循环条件下发生SnO2与Sn的热失配,进而在其界面处产生了极大的交变应力,最终导致SnO2氧化膜破裂,为锡须生长提供了条件.此外,在Sn镀层与Cu基板界面处形成的Sn-Cu金属间化合物(IMC),提供了锡须生长的驱动力.镀层中的Sn原子在压应力的驱动下,沿着氧化物表面裂纹位置挤出,从而释放了压应力形成锡须.在锡须生长的初始阶段,阻力较大,故而速率较慢,在锡须突破表面氧化物层后,阻力较小,故加速了锡须的生长.

关 键 词:器件引脚  纯Sn镀层  锡须  温度循环实验

The Whisker Formation on Pure Sn Coating of Leadframe under Temperature Cycling Condition
ZHANG Jin-song,WU Yi-ping,ZHU Yu-chun,LI Juan-juan,WU Feng-shun,AN Bing.The Whisker Formation on Pure Sn Coating of Leadframe under Temperature Cycling Condition[J].Journal of Shanghai Jiaotong University,2007(Z2).
Authors:ZHANG Jin-song  WU Yi-ping  ZHU Yu-chun  LI Juan-juan  WU Feng-shun  AN Bing
Abstract:Temperature cycling tests were executed to assess the reliability of pure Sn coating.After 500 and 1 000 thermal cycles,Sn whiskers were found to grow initially from the thermal fatigue cracks on the surface with a length in several microns.The mismatch of the coefficient of expansion(CTE) between Sn and SnO_2 produced a very large field of alternative stress in the interface of them.As a result it sheared the SnO_2 and created many cracks on the surface of Sn coating.At the same time,the formation of intermetallic compound(IMC) at the interface between Sn coating and Cu substrate generated a compressive stress to some Sn grains in the coating.This compressive stress was a driving force which promoted Sn atoms out of the surface from the cracks to form Sn whiskers.At the initial stage,the growth rate of Sn whisker was slow because of the retard of oxide.By contrast,when Sn whisker broke the oxide,the growth rate of it was faster.
Keywords:terminals of component  pure Sn coating  Sn whisker  temperature cycling test
本文献已被 CNKI 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号