Effects of different bonding parameters on the electrical performance and peeling strengths of ACF interconnection

Abstract

The effects of different bonding parameters, such as temperature, pressure, curing time, bonding temperature ramp and post-processing, on the electrical performance and the adhesive strengths of anisotropic conductive film (ACF) interconnection are investigated. The test results show that the contact resistances change slightly, but the adhesive strengths increase with the bonding temperature increased. The curing time has great influence on the adhesive strength of ACF joints. The contact resistance and adhesive strength both are improved with the bonding pressure increased, but the adhesive strengths decrease if the bonding pressure is over 0.25 MPa. The optimum temperature, pressure, and curing time ranges for ACF bonding are concluded to be at 180–200 °C, 0.15–0.2 MPa, and 18–25 s, respectively. The effects of different Teflon thickness and post-processing on the contact resistance and adhesive strength of anisotropic conductive film (ACF) joints are studied. It is shown that the contact resistance and the adhesive strength both become deteriorated with the Teflon thickness increased. The tests of different post-processing conditions show that the specimens kept in 120 °C chamber for 30 min present the best performance of the ACF joints. The thermal cycling (−40 to 125 °C) and the high temperature/humidity (85 °C, 85% RH) aging test are conducted to evaluate the reliability of the specimens with different bonding parameters. It is shown that the high temperature/humidity is the worst condition to the ACF interconnection.