Patent ID: 11908905
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 15:
16. A method for forming a semiconductor device, the method comprising:
forming a buffer layer over a substrate, wherein the buffer layer comprises a first group III-V material;
forming an active layer over the buffer layer, wherein the active layer comprises a second group III-V material different than the first group III-V material;
forming a top electrode along a first surface of the active layer;
performing a patterning process on the buffer layer and the substrate to define a plurality of openings and a plurality of pillar structures, such that the pillar structures are laterally offset from one another by a respective opening in the plurality of openings, wherein the patterning process exposes a second surface of the active layer, wherein the second surface is opposite the first surface, wherein widths of the openings are respectively greater than widths of the pillar structures; and
forming a bottom electrode along the substrate, the buffer layer, and the active layer, wherein the bottom electrode directly contacts the second surface of the active layer, wherein the bottom electrode laterally surrounds each pillar structure in the plurality of pillar structures.