摘要
在采用压力约束模式夹持倒装芯片的条件下,实现了热超声倒装键合。通过观测键合过程中的输入超声功率、工具末端和芯片的振幅变化情况,研究了压力约束模式下不同键合参数对键合过程和键合强度的影响规律。试验结果表明:在这种约束模式下,键合力和功率对键合强度具有重要的影响;键合力对金凸点的变形是决定性的;键合强度与输入的超声能量总量有关,过小和过大的超声能量都不能形成好的键合强度,高强度的键合并不需要大的超声功率输入,键合过程中能量主要耗散于工具/芯片间相对运动导致的摩擦做功,并造成了芯片和工具的磨损。
Thermosonic flip chip bonding was realized under the pressure constraint pattern of flip chip. The input ultrasonic power, vibration amplitudes of flip chip and tool tip during bonding process were recorded. The effects of bonding parameters on bonding strength were studied, and related conclusions had been obtained. Firstly, in this chip constraint pattern, the bonding strength is mainly effected by the bonding force and ultrasonic power, and decided by the total energy consumed on bonding interface. Secondly, large ultrasonic power is not necessary for high bonding strength because most energy is consumed by the friction of tool and chip interface, which causes the abrasion of flip chip back and tool tip. Thirdly, the deformation of bumps is chiefly caused by bonding force.
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2006年第18期1944-1947,1954,共5页
China Mechanical Engineering
基金
国家自然科学基金资助重大项目(50390064)
国家重点基础研究发展计划资助项目(2003CB716202)
关键词
热超声倒装键合
压力约束模式
键合参数
键合强度
thermosonic flip chip bonding
pressure constraint pattern
bonding parameter
bonding strength
