Investigations of Fluxless Flip-chip Bonding Using Vacuum Ultraviolet and Formic Acid Vapor Surface Treatment
We studied the effects of surface treatment using vacuum ultraviolet (VUV) and formic acid vapor for SnCu-Au flip-chip bonding. Sn-rich solder bumps are widely used for flip-chip interconnections because of low melting temperature and high mechanical strength. For fine pitch interconnections, surface modification is needed before the bonding process. X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES) were used to investigate Sn surfaces. The results showed how the VUV/O3 surface treatment removes the carbon-based organic contaminants from the Sn surfaces and the formic acid treatment reduces the metal oxides of Sn. Combination of VUV/O3 and formic acid treatments improved shear strength of a bonded sample. The average shear strength of each bump with VUV/O3 and/or formic acid treatment is about twice that of a bump with no treatment.
N. Unami H. Noma K. Sakuma A. Shigetou S. Shoji Mizuno
Waseda University, Okubo 3-4-1, Shinjuku, Tokyo, 169-8855, Japan IBM Research - Tokyo, 1623-14 Shimo-tsuruma, Yamato, Kanagawa 242-8502, Japan IBM Corporation, Systems & Technology Group, 2070 Route 52/B330D/Zip 87P, Hopewell Jct, NY 12533 National Institute for Materials Science (NIMS): 1-1, Namiki, Tsukuba, Ibaraki 305-0044, Japan
国际会议
2011 International Symposium on Advanced Packaging Materials(2011年先进电子封装材料国际会议APM)
厦门
英文
220-225
2011-10-25（万方平台首次上网日期，不代表论文的发表时间）