|Budget Amount *help
¥11,000,000 (Direct Cost : ¥11,000,000)
Fiscal Year 2000 : ¥1,700,000 (Direct Cost : ¥1,700,000)
Fiscal Year 1999 : ¥5,200,000 (Direct Cost : ¥5,200,000)
Fiscal Year 1998 : ¥4,100,000 (Direct Cost : ¥4,100,000)
It is indispensable technology to develop the new microjoining used for the packaging process of IC and LSI of the electronics field. This is the basic technology which achieves the interconnection between integrated circuit electrodes and external leads such as the leadframe, and it is not the exaggeration. However, the materials used there are dissimilar to each other, and the optimization of the interconnection is not easy. Then, in the present study, the bonding mechanism between integrated circuit electrodes and gold fine wires and leads is analyzed and has been clarified from experiments and theoretical calculation results. Especially, material properties (difference between the mechanical properties of the gold fine lead/gold pad), transition of the bonding mechanism by the bonding load increase, the promoting effect of the wire deformation with the pad temperature increase, and the effects of the bonding tool shape on the interconnection formation, etc.were clarified. And also,
the analysis for adhesional bonding mechanism at room temperature which is expected to be very important in the near future were carried out in the present study, and the increase phenomenon of the bond strength with the time after bonding was investigated and the mechanism was clarified. The results that were concretely obtained in the present study are classified into the following 8 points.
1) The effect of material properties, bonding pressure, bonding temperature on the bonding process were analyzed.
2) The analysis of the interfacial diffusion behavior between pad and fine wires and the change in the stress distribution with time.
3) The transition of adhesional bonding mechanism with the bonding load increase.
4) The numerical simulation of deformation process of pad and gold fine wire.
5) The analysis of the effect of the bonding tool on the bonding process.
6) Effect on the bonded interface extension of the pad thickness and effectiveness of the gold bump for the microjoining.
7) Theory of adhesional bonding process between gold fine wire and pad, and also the quantification.
8) Numerical examination of the bonded interface migration phenomenon and the abnormal formation of the grain boundary groove. Less