银丝键合烧球参数对键合质量的影响

Effect of Electronic Flame Off Parameters on the Bonding Using Silver Wire

经键合试验,测试焊线挑断力和焊球推力,观察焊球和电极界面形貌,研究了烧球电流和时间对银键合丝键合质量的影响。结果表明,随烧球电流增大、时间延长,键合无空气焊球(FAB)直径增大;FAB球颈晶粒尺寸是电流和时间共同作用的结果,晶粒尺寸越大、挑断力越小,18 mA-1.0ms烧球所得挑断力最小;在FAB尺寸相近的前提下随烧球电流减小,焊球推力降低,键合过程中电极易受损导致电极材料挤出率增大;高电流-短时间(23 mA-0.6 ms)烧球有利于银丝获得较好的键合质量。

The effect of electronic flame off current and time on the bonding quality of silver wire was studied via bonding,wire pulling and ball shearing test.Results showed that diameter of the FAB enlarged with the increase of current and time.Grain size at the ball neck was the combined result of current and time.Larger grain would lead to smaller pulling force,thus the pulling force reached the minimum value at18mA-1.0ms.With the current decreasing on the basis of similar FAB size,ball shear force decreased and the percentage of gold bleeding out increased as a result of electrode damage.The bonding at a higher current and for a shorter time(23mA-0.6ms)resulted in comprehensively better quality.