【摘要】 用实验和有限元的分析方法研究0．05mm～0．125mm铝线的引脚跟断裂问题。结果显示由于引线键合工艺、注塑工艺以及回流焊中封装体各部分不同的热膨胀系数引起的热应力和塑性变形是产生引脚跟断裂的主要因素。模拟不同的回流焊温度曲线(220℃、240℃、260℃)对铝线的影响,发现在铝线引脚跟处应力和应变最大,而且随着温度的上升,铝线引脚跟处的塑性变形会提高20％,这对铝线的疲劳损伤是很严重的。更多还原

【Abstract】 We investigate the heel crack both in experimental and FEA simulation study for the 0.05mm～0.125mm aluminum wire.The result shows that the plastic strain at the heel region induced by wire bonding process, molding process and the thermal stress and strain in solder reflow are the main causes of heel crack.With respect to the trend of lead free,the simulation is also processed under the three temperature hierarchies with different peak reflow temperature(220℃,240℃,260℃)and wetting time.From thermal stress and strain distributions,it can been seen that,during the fellow,the heel region of the wire is endured larger stress and plastic strain than other areas,and with the peak reflow temperature and wetting time increasing,the plastic strain also increases about 20%,which is very critical for material fatigue.更多还原