Highly Reliable Solderless Contact with Press-fit Technology for Power Modules

Abstract Press-fit technology has been expected as a mounting technique instead of soldering in power electronics. To apply press-fit technology to power modules, the basic behavior of the contact resistance and an interface reaction of the press-fit contact are studied. Further, maintaining a stable contact force is important to maintain a low contact resistance. Factors that reduce the contact force include the displacement by the geometric tolerance of the pin and through-hole of the printed circuit board, and the thermal cycle load. We solved the problem by designing a new press-fit pin structure that provides the constricted portion for the body part of the press-fit pin, and clarified by thermal cycle test on power modules.