Effects of ultrasonic bonding process on polymer-based anisotropic conductive film joints in chip-on-glass assemblies

• Published in: Polymer testing 2011-05, Vol.30 (3), p.318-323
• Main Authors: Lin, Y.C., Jin, Hao, Fang, Xiao-Nan
• Format: Article
• Language: English
• Subjects: Anisotropic conductive film (ACF); Anisotropy; Application fields; Applied sciences; Assemblies; Bonding; Bonding strength; Chip-on-Glass (COG); Cog; Cures; Curing degree; Electronics; Exact sciences and technology; Microelectronic fabrication (materials and surfaces technology); Optimization; Polymer industry, paints, wood; Polymeric films; Process parameters; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Technology of polymers
• ISSN: 0142-9418; 1873-2348
• DOI: 10.1016/j.polymertesting.2010.12.006

Polymer-based anisotropic conductive film has become widely used in many electronic packaging interconnect applications. In this study, thermosonic flip chip bonding technology for anisotropic conductive film (ACF) joints in Chip-on-Glass (COG) assemblies is investigated. The effects of ultrasonic bonding process parameters on the degree of cure and bond strength of polymer-based anisotropic conductive film joints are discussed. Results show that (1) the bond strength and degree of cure both increase with increase of the bonding time and the optimum bonding time is 3 s; (2) the effects of the bonding force on the bond strength are not significant; (3) the bond strength of the ACF joints firstly increases and then rapidly decreases when the ultrasonic power is continuously increased; (4) the degree of cure of ACF material increases with increase of the ultrasonic power. When the ultrasonic power is 3.52 W, the degree of cure of ACF material can reach 94%. Hence, the optimum value of ultrasonic power is about 3.5 W for the studied COG assembly.