Katsuyuki Sakuma, Spyridon Skordas, et al.
ECTC 2014
We studied the feasibility of using vacuum ultraviolet (VUV) treatment as a surface improvement technique with Au-Au flip-chip bonding. For finepitch electrical interconnections in three-dimensional (3D) stack applications, robust and reliable bonding is desirable; in this case, surface modification treatment is needed before the bonding process. A VUV surface treatment was used to remove organic contaminants. Samples of electroplated Au pads were examined by X-ray photoelectron spectroscopy (XPS) to evaluate the chemical composition of the Au surfaces. The XPS results revealed that the carbon-based contaminants on the surface were removed by the VUV treatment. The shear strength of the bonded sample was also improved. The average shear strength of a bump with VUV treatment is 1.6 times larger than that of a bump without VUV treatment. Cross-sectional scanning electron microscopy (SEM) images of the bonded samples confirmed the absence of voids and cracks. The results show that VUV treatment has clear effects on Au-Au flip-chip bonding. © 2010 The Japan Society of Applied Physics.
Katsuyuki Sakuma, Spyridon Skordas, et al.
ECTC 2014
Katsuyuki Sakuma, Kazushige Toriyama, et al.
ECTC 2011
Katsuyuki Sakuma, Roy Yu, et al.
IEDM 2024
Akihiro Horibe, M.-C. Paquet, et al.
ECTC 2011