<4D6963726F736F667420576F7264202D2033362D31342E20B7A4A7CEBE5ABC4CBB50B657ADB5AA69BE5ABD75B1B5A658B94CB57BA4A7ACE32E646F63>181

Wire Bonding

ABSTRACT
Integrated circuit packaging is a backend process of semiconductor industry. Due to
the modeling diversification of assembly, process accuracy is required to higher quality.
Ultrasonic wedge bonding is one of the most important interconnection techniques for
IC dies inner circuits with the outer world for the power and signal transportation. There
is a significant effect of the bonding parameters to the joint quality and reliability.
Therefore, the chemical etching method observes the bond configuration and interface
characteristics. It is found that the bond interface form the oval-shaped with the increase
of the ultrasonic power relation, furthermore, the actual joining position develop from
the bond peripheral to the central, and to the whole bond interface. The bond area is
increased in the substrate, and the bond strength will be increased relatively.

182


(Tape automated bondingTAB)(Flip chipFC)
[1]
(Pad)
bondingT/S)
(Ball grid arrayBGA)

(Pull tester)
(60KHz 110KHz)
Li [4] Al-Ni
Cheung[5]
200

(Heel)
183



PCB PCB

60KHz(Wire feed angle) 30 o ()
(Al+Si 1)(WC2130-2025-L)() 99.99
(Cermet2130-2020-L-CC-CG BKCER)()
31.75µm

PCB


184
F ( F1 )
( F2 )(Neck)
(Tail consistency)(BR)

20mw 70mw 5.2gf
0.9 PCB
110mw
PCB
() 110mw
SEM110mw
185
170mw()
5gf 1.8
(~) 110mw

((f))
()
σe < σy
X
X2 X3
σe1 σe2
X2 X1

7.2gf 35ms
95gf 110mw 5.3gf


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Journal of China Institute of Technology Vol.36-2007.6
187
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188
300~500
150~250

Bonding time
Ultrasonic power
Bonding force

Bonding time
Ultrasonic power
Bonding force
189
191
Def orm




Journal of China Institute of Technology Vol.36-2007.6
193
80 100
120 140
160 180
P u l l t e s t ( g f )
Defo rmatio
Journal of China Institute of Technology Vol.36-2007.6
195





( 19ms 90gf
(a)70mw (b)90 mw (c)110 mw (d)130 mw (e)150 mw (f)170 mw)
(a) (b)
(c) (d)
(e) (f)
( 35ms 95gf
(a)90mw (b)110 mw (c)130 mw (d)150 mw (e)170 mw (f)200 mw)
(a) (b)