Electrical Properties of Ultrasmall Low Temperature Solder Joints for LCD Driver ICPackaging ApplicationsElectrical Properties of Ultrasmall Low Temperature Solder Joints for LCD Driver ICPackaging Applications

Abstract

We developed a fine pitch COG technique using the low temperature solder bumps for LCD driver IC packaging applications. Using the eutectic Bi-Sn and the eutectic In-Ag solder bumps of 80-50 ㎛ pitch sizes, a ultrafine solder joint between IC and glass substrate was successfully made at or below 160℃. The contact resistance of the solder joint of 50 ㎛ pitch was 42 mΩ, which was much lower than that of the joint made using the conventional ACF bonding technique.