Patent ID: 11929420
Assignee: WOLFSPEED, INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 17:
18. A semiconductor device, comprising:
a silicon carbide semiconductor layer structure that comprises a first conductivity type drift region, and first and second well regions in an upper surface of the first conductivity type drift region, the first and second well regions separated by a JFET region;
a gate dielectric layer on the silicon carbide semiconductor layer structure, the gate dielectric layer comprising a base gate dielectric layer that is on the silicon carbide semiconductor layer structure and a capping gate dielectric layer on the base gate dielectric layer, the capping gate dielectric layer comprising a different material than the base gate dielectric layer, wherein a dielectric constant of the capping gate dielectric layer is higher than a dielectric constant of the base gate dielectric layer, and the capping gate dielectric layer is thinner than a portion of the base gate dielectric layer that is below the capping gate dielectric layer; and
a gate electrode on the gate dielectric layer opposite the silicon carbide semiconductor layer structure.