Thermal stability performance of anisotropic conductive film at different bonding temperatures

In this work the effect of different bonding temperatures on the thermal stability of anisotropic conductive films (ACFs) was investigated. A thermogravimetric analyzer (TGA) was utilized to determine the thermal decomposition temperature of ACF. The experimental results showed that the temperature for maximum decomposition rate of ACF, Tm decreased with increasing bonding temperature. The results obtained from Fourier transform infrared spectroscopy (FTIR), which was used to examine the curing degree and also chemical changes in the ACF, showed some networks scissoring happened on C–N bond during the bonding process. This was the main reason why the ACF bonded at high temperature 225.0 C, gave relatively low thermal stability. Four point probe was used to measure the contact resistance performance before and after thermal aging at 260 and 300 C. The contact resistance results suggested that ACF bonded with 10 s at 205.0 C, yielding a curing degree of 85.0% was the best bonding parameter to obtain a low contact resistance after thermal aging. FTIR results showed there was a significant increase in the absorbance peak of carbonyl group after thermal aging. Thermal oxidation reactions which were taken place at high bonding and aging temperature had broken the polymer networks in the ACF and caused electrical failure. 2003 Elsevier Ltd. All rights reserved.