New Failure Mechanism in High Temperature Resin Materials

Green electronics for electrical driving or solar energy application need high temperature substrates because the next generation of power semiconductors is based on wide-bandgap semiconductors (WBG), e.g. GaN or SiC. These WBG materials support the possibility of higher switching currents and high frequency applications. Driven by the high-voltage blocking resistance of these WBG high temperatures up to 250°C are possible. For reduced switching losses new concepts for low inductive commutation cells are already developed, e.g. the wire-bond-less PCB embedding technology. So far, an affordable high temperature compatible resin material was not available and ceramics or lead frame solutions are state of the art. The present work shows the first results of a new resin material with a T
_g
> 200°C (~400°F) in combination with a high temperature PCB technology (Printed Circuit Board). The new Epoxy resin material HELP-I and the new Benzoxazine resin material HELP-H are suitable for peak temperatures up to 200°C. In addition to the known oxidation, new failure mechanisms are observed and microcracks in the resin are described by a simulation model. Based on these simulated and experimental validated data the optimization will be presented. This knowledge is now enabling organic substrate with operating temperature up to 200°C for the use of SiC and GaN. First test results will be shown, the resin material properties and also the possibility of SiC and GaN embedding into the new resin will be discussed.