Effect of capillary tip shape on deformation and bondability in Au wire bonding

Hiroyuki Saiki¹, Yasuo Marumo^1a, Hiroshi Nishitake², Tetsuhiro Uemura¹, Takahiro Yotsumoto²

¹Department of Mechanical System Engineering, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 Japan.
²a Sony Semiconductor Kyushu Co. Ltd., Japan.

DOI:

https://doi.org/10.7494/cmms.2007.1.0130

Abstract:

Au wire bonding is a process for connecting a lead frame and a semiconductor chip in electronic packaging. In Au wire bonding, an Au ball is pressed into an Al terminal by a capillary. It is required to reduce the bonding area to as small as possible while maintaining the strength of bonding. This paper shows effects of capillary tip shape on bondability and deformation of Au ball and Al film in Au wire bonding. To study the change of bonding condition along with the change of capillary shape, typical capillaries were selected and their bonding processes were analyzed. Bonding reliability tended to become high as the maximum ball height became small, namely, as the volume of the collapsed periphery became large, and also as the bulge at the periphery of bonding and the contact pressure became large. The superiority of these capillaries can be roughly evaluated.

Cite as:

Saiki, H., Marumo, Y., & Nishitake, H. Uemura, T., Yotsumoto, T., (2007). Effect of capillary tip shape on deformation and bondability in au wire bonding. Computer Methods in Materials Science, 7(1), 119 – 123. https://doi.org/10.7494/cmms.2007.1.0130

Article (PDF):

Keywords:

Wire bonding, Bondability, Capillary tip shape, Deformation analysis, Au ball

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