Method of fabricating slanted field-plate GaN heterojunction field-effect transistor

摘要

A method of forming a slanted field plate including forming epitaxy for a FET on a substrate, forming a wall near a drain of the FET, the wall comprising a first negative tone electron-beam resist (NTEBR), depositing a dielectric over the epitaxy and the wall, the wall causing the dielectric to have a step near the drain of the FET, depositing a second NTEBR over the dielectric, wherein surface tension causes the deposited second NTEBR to have a slanted top surface between the step and a source of the FET, etching anisotropically vertically the second NTEBR and the dielectric to remove the second NTEBR and to transfer a shape of the slanted top surface to the dielectric, and forming a gatehead comprising metal on the dielectric between the step and the source of the FET, wherein the gatehead forms a slanted field plate.

主权项

1. A method of forming a slanted field plate comprising:
forming epitaxy for a field effect transistor (FET) on a substrate; forming a wall on the epitaxy near a drain of the FET, the wall comprising a first negative tone electron-beam resist; depositing a dielectric over the epitaxy and the wall, the wall causing the dielectric to have a step near the drain of the FET; depositing a second negative tone electron-beam resist over the dielectric, wherein surface tension causes the deposited second negative tone electron-beam resist to have a slanted top surface between the step and a source of the FET; etching anisotropically vertically the second negative tone electron-beam resist and the dielectric to remove the second negative tone electron-beam resist and to transfer a shape of the slanted top surface to the dielectric between the step and the source of the FET; and forming a gatehead comprising metal on the dielectric between the step and the source of the FET; wherein the gatehead forms a slanted field plate.