Improvement in Copper-Resin Bond Strength after High-Temperature Testing Using C–H–Si Thin Film

The bonding between copper and epoxy resin is investigated using a C–H–Si thin film to achieve highly adhesive and reliable bonding between the resin mold and the copper substrate in power modules. In this study, high-temperature (473 K) testing is performed to improve the reliability of this junction after high-temperature operation. The bond strength decreases and delamination occurs at the film–copper interface after high-temperature testing. The decrease in bond strength may be due to the decrease in the film–copper interfacial strength because of the decrease in the binding force between copper and oxygen upon heating. When Fe and Cr, which have high oxygen bond disassociation energies, are intercalated at the film–copper interface, the bond strength improves after high-temperature testing and a bond strength above 30 MPa was retained after 1000 h.