Chip bonding on non-rigid and flexible substrates with new stepped processes

Reliable interconnection of electrodes to the plastic-based display with an isotropic conductive films (ACFs). of, which the conductive particles were similar in elasticity to the substrates, was accomplished. The contact resi stance value was maintained even while the junction was stressed under sudd en changes in temperature and pressure. It was found that the conduction fa ilure was caused by the action of a complex mechanism on the changes of a j oint structure. The major driving factor seems likely to be defects in the transparent electrodes due to the thermal strain of substrates and penetrat ion of conductive particles. Conductive particles with elasticity similar t o that of the plastic substrates did little damage to the transparent elect rodes on the substrates, and low temperature and pressure under a stepped p rocess did not bring about their deformation either. As a result, a highly reliable interconnect with a very low contact resistance was realized.