Patent ID: 7857509

Claim:
A substrate subassembly comprising: a ceramic wafer having first and second opposed metallized major faces; a first metal tab on the first metallized face that extends away from the ceramic wafer for electrical connection to a first terminal member; a semiconductor switching device electrically conductively bonded to the first metallized face of the ceramic wafer, wherein the semiconductor switching device includes electrodes on a first surface; a first ceramic layer bonded to a portion of the first metallized face of the ceramic wafer adjacent the semiconductor switching device, the first ceramic layer having a metallized first surface; a second metal tab on the metallized first surface of the first ceramic layer that extends away from the ceramic wafer for electrical connection to a second terminal member; a first metal layer conductively bonded to the electrodes on the first surface of the semiconductor switching device and also to the metallized first surface of the first ceramic layer; a second ceramic layer bonded to the first metal layer, the second ceramic layer being disposed over the semiconductor switching device; a second metal layer bonded to the second ceramic layer, wherein the first metal layer, the second ceramic layer, and the second metal layer form an interconnect that approximately matches a thermal coefficient of expansion of the semiconductor switching device; and a temperature sensor coupled to the semiconductor switching device, the temperature sensor configured to measure the temperature of the semiconductor device.