Title :
The chip-on-board bonding using non-conductive film and metallic bumps by the surface activated bonding method
Author :
Wang, Ying-Hui ; Suga, Tadatomo
Author_Institution :
Sch. of Eng., Univ. of Tokyo Hongo, Tokyo
Abstract :
To reduce the thermal stresses generated in COB interconnection using NCF and flip-chip metallic bumps in conventional high-temperature processes, a surface activated bonding method is used in this study. The bonding feasibility is confirmed at 100-150degC in ambient air using Ar-RF plasma pretreatment under low vacuum. The surface conditions before and after activation are analyzed by X-ray photoelectron spectroscopy. Carbon contaminants are removed by this activation. The optimized bonding temperature, pressure and time is detected to be 150degC, 150 MPa, and 180 s, respectively. The die shear strength is around 90 MPa and the bond yiled reaches 100%. In bonding of the micro-bumps, the properties of NCF should be considered, such as the thermosetting time and temperature.
Keywords :
X-ray photoelectron spectra; bonding processes; chip-on-board packaging; decontamination; plasma materials processing; shear strength; thermal stresses; X-ray photoelectron spectroscopy; bonding temperature; carbon contaminants; chip-on-board bonding; die shear strength; flip-chip metallic bumps; interconnection; nonconductive film; plasma pretreatment; surface activated bonding method; temperature 100 degC to 150 degC; thermal stresses; thermosetting temperature; thermosetting time; time 180 s; Argon; Bonding; Gold; Integrated circuit interconnections; Plasma temperature; Plasma x-ray sources; Semiconductor films; Spectroscopy; Surface contamination; Thermal stresses;
Conference_Titel :
VLSI Packaging Workshop of Japan, 2008. VPWJ 2008. IEEE 9th
Conference_Location :
Kyoto
Print_ISBN :
978-1-4244-3498-5
DOI :
10.1109/VPWJ.2008.4762217
