Improving the Encapsulation Reliability of Epoxy Sealing Interface through Surface Treatment

Preventing the interface delamination between epoxy molding compound(EMC) and packaging sealing interfaces plays an important role in the reliability of epoxy sealing devices, especially for the large-area power module which are welded after transfer molding. When these power modules encapsulated with EMC are subjected to reflow soldering, significant thermal stress is generated because of the difference in the thermal expansion coefficient of each materials inside the power module. As a result, the epoxy resin delaminates from AMB substrate which will adversely affects the reliability of the device. In this paper, chemical etching roughening treatment and chemical surface treatment were developed. This surface treatment technology shows very excellent effect in improving the bonding force of the plastic sealing material and inhibiting the delamination causing by welding, which also show promising engineered mass producibility.