Patent ID: 8653590

Claim:
A trench MOSFET formed in a body of semiconductor material comprising: a substrate made of a first semiconductor material and with a first type of conductivity, the first semiconductor material having a first bandgap, the substrate corresponding to the drain region of the trench MOSFET; an epitaxial region made of the first semiconductor material and with the first type of conductivity, which overlies the substrate and defines a first surface; a first epitaxial layer made of a second semiconductor material, which overlies the first surface and is in direct contact with the epitaxial region, the second semiconductor material having a second bandgap narrower than the first bandgap; wherein the body further comprises a deep region of a second type of conductivity including first and second deep region portions, the first and second deep region portions extending underneath the first surface and within the epitaxial region; wherein a trench extends from a second surface of the first epitaxial layer through the first epitaxial layer and through the first surface of the epitaxial region into the epitaxial region; wherein a gate region is formed extending from the second surface within the trench; and wherein source regions are formed surrounding the gate region and extending from the second surface into the first epitaxial layer.