GaN-based Schottky barrier diode with field plate
View Patent ↗A method for fabricating a III-nitride semiconductor device includes providing a III-nitride substrate having a first surface and a second surface opposing the first surface, forming a III-nitride epitaxial layer coupled to the first surface of the III-nitride substrate, and removing at least a portion of the III-nitride epitaxial layer to form a first exposed surface. The method further includes forming a dielectric layer coupled to the first exposed surface, removing at least a portion of the dielectric layer, and forming a metallic layer coupled to a remaining portion of the dielectric layer such that the remaining portion of the dielectric layer is disposed between the III-nitride epitaxial layer and the metallic layer.
1. A III-nitride semiconductor device comprising:
an active region for supporting current flow during operation of the III-nitride semiconductor device, the active region comprising a III-nitride epitaxial material; and
a field plate region physically adjacent to the active region, the field plate region including:
the III-nitride epitaxial material;
a spin-on dielectric material in physical contact with a first surface and a second surface of the III-nitride epitaxial material, wherein the second surface is angled with respect to the first surface; and
a metal coupled to the spin-on dielectric material.
2. The III-nitride semiconductor device of claim 1 wherein an angle between the first surface and the second surface is between 45° and 90°.
3. The III-nitride semiconductor device of claim 1 wherein a first surface of the spin-on dielectric material is angled with respect to a second surface of the spin-on dielectric material.
4. The III-nitride semiconductor device of claim 3 wherein an angle between the first surface of the spin-on dielectric material and the second surface of the spin-on dielectric material is less than 45°.
5. The III-nitride semiconductor device of claim 3 wherein the first surface has a varying slope with respect to the second surface.
6. The III-nitride semiconductor device of claim 1 wherein the metal comprises a Schottky metal structure coupled with a portion of the III-nitride epitaxial material, the Schottky metal structure forming a Schottky barrier with the portion of the III-nitride epitaxial material.
7. The III-nitride semiconductor device of claim 1 wherein the spin-on dielectric material includes at least one of benzocyclobutene (BCB) or spin-on glass (SOG).