Ultrasonic Micro-welding Using High-Frequency and Complex Vibrations

1.超声焊接高频系统在90-780千赫的频率特性已经表明，与60千赫的传统系统相比，高频系统变得非常有效。所需振动速度v和位移幅值xi随频率的增加而减小。v=Af^<-0.6>, xi=Bf^<-1.49> A，B：常数。在780 kHz时0.04 mum的峰至零值是60 kHz时的1/30。复合振动轨迹焊头是改善焊接性能的有效方法。采用190khz圆形和方形振动轨迹的超声焊丝的焊接特性和温升与600khz线性振动轨迹的焊接特性和温升相当。与线性轨迹相比，以相同或不同频率从椭圆到圆形或从矩形到方形振动的复杂振动焊接头，在更短的焊接时间内，在更小的振动幅度下，在更宽的良好焊接区域内，有效地连接了焊接试样。提出了利用陶瓷毛细管进行超声球键合的高频纵向到复杂横向振动系统，频率为160 kHz ~ 1 MHz。采用400 kHz纵向-复合横向振动系统成功连接了直径为0.1 mm的铝丝试件。发现传统陶瓷毛细管在400 kHz - 1 MHz的频率下沿毛细管有两个或三个节点振动。焊接尖端处得到的振动速度幅值足以保证焊接成功。研究结果表明，超声焊线的焊接性能得到了明显改善。开发了两种振动频率的高频焊接系统，例如160 kHz和500 kHz。采用高频和复杂振动系统的自动系统正在进行工作，超高频焊接特性也在进行研究。

1.Frequency characteristics of ultrasonic welding High-frequency systems at 90-780 kHz have been shown that high-frequency systems become to be significantly effective in comparison to a conventional system at 60 kHz. The required vibration velocity v and displacement amplitude xi decrease as frequency increases. v=Af^<-0.6>, xi=Bf^<-1.49> A,B : constants. A peak-to-zero value of 0.04 mum at 780 kHz is 1/30 of that at 60 kHz.2.Complex vibration locus welding tip was found to be effective for improving the welding characteristics. Welding characteristics and temperature rise of ultrasonic wire bonding using 190 kHz circular and square vibration loci are equivalent to these of a 600 kHz linear vibration locus. Complex vibration welding tips which vibrate in elliptical to circular or rectangular to square shapes at either the same or different frequencies effectively joined welding specimens successfully in shorter welding times, under smaller vibration amplitudes, and over wider good welding areas in comparison to linear locus.3.High-frequency longitudinal to complex transverse vibration systems 160 kHz - 1 MHz were proposed for ultrasonic ball bonding using a ceramic capillary. Aluminum wire specimens of 0.1 mm diameter were successfully joined using the 400 kHz longitudinal-complex transverse vibration system.4.The conventional ceramic capillaries were found vibrating with two or three nodes along the capillary at 400 kHz - 1 MHz. The vibration velocity amplitude obtained at the welding tip is sufficient for successful welding.5.The welding characteristics of the ultrasonic wire bonding were found to be significantly improved by these results obtained by this research. The high-frequency welding systems available in two vibration frequencies, for an example 160 and 500 kHz, were developed.6.The automatic system using high-frequency and complex vibration systems is under working, and also welding characteristics using ultra-high frequency is under investigation.