Patent ID: 11881512
Assignee: INFINEON TECHNOLOGIES AG
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method of manufacturing a semiconductor device, the method comprising:
providing a silicon carbide substrate, wherein a gate trench extends from a main surface of the silicon carbide substrate into the silicon carbide substrate and wherein a gate dielectric is formed on at least one sidewall of the gate trench; and
forming a gate electrode in the gate trench, the gate electrode comprising a metal structure and a semiconductor layer between the metal structure and the gate dielectric,
wherein the silicon carbide body comprises a drift structure, a source region and a body region, wherein the body region forms a first pn junction with the drift structure and a second pn junction with the source region, wherein the source region is positioned between the body region and the first surface, and wherein the body region is in contact with the gate dielectric,
wherein the metal structure comprises an upper surface that is covered by an interlayer dielectric,
wherein the metal structure vertically extends from the upper surface to a bottom of the metal structure that is disposed below the second pn junction,
wherein the metal structure comprises a first layer in contact with the semiconductor layer and a fill structure that contacts the first layer, wherein the first layer separates the fill structure from the semiconductor layer,
wherein the first layer includes a first transition metal, and
wherein the fill structure includes a second transition metal that is different from the first transition metal.