Studies on Ultrasonic Micro Welding Using High-Frequency Vibration

研究了27 ~ 800 kHz的高频和复合振动超声焊接系统的振动特性和焊接特性。具有椭圆到圆形或矩形到正方形轨迹的高频复杂振动系统对于包括相同和不同金属试样的各种试样的超声焊接、半导体尖端的直接焊接和各种电子器件的无焊料封装是有效的。该复杂振动系统由一个带狭缝的一维弯扭振动转换器、一个阶梯形变幅杆和一个作为驱动源的纵向振动换能器组成。27 kHz和100 kHz的复合振动焊嘴具有6 mm至8 mm见方的足够的面积用于各种焊接试样。厚度为0.3 mm至1.0 mm的铝板试样成功连接，焊缝强度几乎等于铝试样强度，且与试样方向无关。100 kHz系统所需的振动幅度小于27 kHz系统，此外，提出了40 kHz至200 kHz的复合横向振动系统，以获得与具有大量凸块的大型半导体焊尖相对应的10 mm至20 mm见方的大焊尖面积，以连接到基板。该复合横向振动系统由一个21 mm见方的阶梯形复合横向振动杆、两个处于横向振动环位置上的垂直交叉的纵向振动系统和一个带静压源的焊接框架组成。复合振动源固定在焊接框架中的横向节点位置。40 kHz复合振动焊接头以超过1.0 mm/s（峰至零值）的振动速度振动，并在整个焊接头上均匀振动。

The vibration and welding characteristics of high-frequency and complex vibration ultrasonic welding systems of 27 kHz to 800 kHz were studied. High-frequency and complex vibration systems, which have elliptical to circular or rectangular to square locus, are effective for ultrasonic welding of various specimens including the same and different metal specimens, and for direct welding of semiconductor tips and packaging of various electronic devices without solder. The complex vibration systems consist of a one-dimensional longitudinal-torsional vibration converter with slitted parts, a stepped horn and a longitudinal vibration transducer as a driving source. The complex vibration welding tips of 27 kHz and 100 kHz have enough area of 6 mm to 8 mm square for various welding specimens. Aluminum plate specimens of 0.3 mm to 1.0 mm thickness were successfully joined with weld strengths almost equal to aluminum specimen strength, and independent to the specimen direction. Required vibration amplitude of 100 kHz system is less than that of 27 kHz system.Furthermore, the longitudinal-complex transverse vibration systems of 40 kHz to 200 kHz were proposed to obtain large welding tip area such as 10 mm to 20 mm square corresponding to large semiconductor tips with large number of bumps for connecting to the substrates. The longitudinal-complex transverse vibration system consists of a stepped complex transverse vibration rod of 21 mm square, two longitudinal vibration systems which are in the transverse vibration loop positions crossed at a right angle, and a welding frame with a static pressure source. The complex vibration source is fixed at a transverse nodal position in the welding frame. The 40 kHz complex vibration welding tip vibrates at vibration velocity of more than 1.0 mm/s (peak-to-zero value) and vibrates uniformly throughout the tip.