Solid State Science and Technology, Vol. 16, No 2 (2008) 232-239

ISSN 0128-7389

Corresponding Author:



S. Abdullah, Z. A. Aziz, I. Ahmad, M. F. Abdullah and M.F. Mod Yunoh

Faculty of Engineering, Universiti Kebangsaan Malaysia,

43600 UKM Bangi, Selangor



The movement of the wire capillary is controlled by looping parameters that will generate the wire bending, compressive and tensile stresses that will cause necking problem. The wire looping parameters that affect the wire loop formation, especially at the neck area were studied in this paper. The wires were bond with different kink height, reverse motion and loop factor using thermosonic technique. Design of experiment using the 2k factorial was applied and performed nine combinations of looping formations. Before molding process, the units were observed using Scanning Electron Microscopy (SEM). The wire pull test experimental results are carried out in order to check the strength of the neck and analyzed using the statistical method. The results shown that run 1 gave the lowest wire pull reading, that is 84.847 mN, compare to other runs. Run 1 has the lowest wire pull reading because it formed the lowest loop height that affected the neck strength in becoming weaker. Moreover, statistical method using main effect plot applied to observe the trend of neck strength due to the value of looping parameter.



[1]. G. G. Harman, (1997), Wire Bonding in Microelectronics: Materials, Process, Reliability and Yield, 2nd Edition, McGraw-Hill.

[2]. I. W. Qin, (2005), Wire Bonding Tutorial, Advanced in Bonding Technology, Advanced Packaging.

[3]. Saraswati, Theint E. P. P., Stephan D., Wulff F. W., Breach C. D. & Calpito D. R. M.,(2004), Looping Behaviour of Gold Ballbonding Wire, Kulicke & Soffa (S. E. A) Pte. Ltd.

[4]. B. Shu, (1991), Fine pitch wire bonding development using a new multipurpose, multi-pad pitch test die, Proc. of the 41st Electronic Component and Technology Conference, Atlanta, pp. 511-518.

[5]. B. Shu, (1992) Wire Bond Development for High-pincout Surface Mount, Proc. of the 42nd Electronic Component and Technology Conference, San Diego, pp. 890898.

[6]. B. Shu, S.S. Lee & R. Groover, (1995), Wire bond loop profile development for fine pitch-long wire assembly, IEEE Trans. Semiconductor Manufacturing Technology Part A 18 (1): 230234.