Patent ID: 11973134
Assignee: MITSUBISHI ELECTRIC RESEARCH LABORATORIES, INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 15:
16. A transistor, comprising:
a source and a drain, such that a bottom surface of the source and a bottom surface of the drain are at a first horizontal plane of the transistor;
a gate, wherein the gate is at a second horizontal plane of the transistor, wherein the second horizontal plane is higher than the first horizontal plane;
a first region under the first horizontal plane, such that the first region includes a first portion of a base substrate layer, a first portion of a buffer layer over the first portion of the base substrate layer, a first three Nitride (III-N) layer over the first portion of the buffer layer and a second III-N layer over the first III-N layer, wherein the second III-N layer has a first spontaneous polarization charge higher than a second spontaneous polarization charge of the first III-N layer, and wherein the first horizontal plane is arranged above a top surface of the second III-N layer;
a second region under the gate, such that the second region includes a second portion of the base substrate layer, a second portion of the buffer layer over the second portion of the base substrate layer, the first III-N layer over the second portion of the buffer layer, and the second III-N layer over the first III-N layer, and a third III-N layer directly on the second III-N layer, wherein selective locations of the third III-N layer extend vertically through the second III-N layer and into one or more portions of the first III-N layer along a direction perpendicular to the first horizontal plane and the second horizontal plane, wherein portions of the selective locations of the third III-N layer that extend into the one or more portions of the first III-N layer are implanted with Magnesium, wherein the third III-N layer is doped P-type, wherein a top surface of the third III-N layer extends above a top surface of the source and a top surface of the drain, and wherein the third III-N layer extends continuously and horizontally under the gate in a third horizontal plane parallel to the first horizontal plane and the second horizontal plane without intersecting the source and the drain.