Vibration characteristics of capillary in wire bonder

C. M. Hu, N. Q. Guo, J. D. Yu, S. F. Ling

Research output: Contribution to conferencePaper

6 Citations (Scopus)


Currently ultrasonic wire bonders with precision capillary tips are widely used for bonding wires to IC chips and circuits. In the bonding process, a metallurgical bond is achieved through the proper transmittal of ultrasonic energy under pressure to the bond surface at a constant ultrasonic frequency (60 kHz and above depending on materials of the wire used). However, the quality and strength of a bond are affected significantly by the change of the vibration characteristics of the bonding capillary and system during bonding process, which is yet well understood. Research effort has been made to develop non-contact, non-perturbative and low-cost monitoring device for measurement of vibration, in the aim for improving bonding quality control. This paper reports the initial study on the understanding of the capillary vibration. The vibration characteristics of capillary such as natural frequencies and vibration modes are first analyzed using finite element method. The predicted displacement profile along the tip of the capillary was compared with the measurement using a non-contact laser vibro-meter, and good agreement between the prediction and measurement was obtained.

Original languageEnglish
Number of pages4
Publication statusPublished - 1998
Externally publishedYes
EventElectronics Packaging Technology Conference 1998 - Singapore, Singapore
Duration: 8 Dec 199810 Dec 1998
Conference number: 2nd (Proceedings)


ConferenceElectronics Packaging Technology Conference 1998
Abbreviated titleEPTC 1998
Internet address

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