US Patent 7427326 Minimizing degradation of SiC bipolar semiconductor devices

A method of forming a bipolar device includes forming at least one p-type layer of single crystal silicon carbide and at least one n-type layer of single crystal silicon carbide on a substrate. Stacking faults that grow under forward operation of the device are segregated from at least one of the interfaces between the active region and the remainder of the device. The method of forming bipolar devices includes growing at least one of the epitaxial layers to a thickness greater than the minority carrier diffusion length in that layer. The method also increases the doping concentration of epitaxial layers surrounding the drift region to decrease minority carrier lifetimes therein.