Method for manufacturing epitaxial substrate by irradiating a surface of a group iii nitride semiconductor layer with ultraviolet light in an atmosphere containing oxygen
AssigneesSumitomo Electric Device Innovations, Inc., Sumitomo Electric Industries, Ltd.
InventorsKohei Miyashita, Takeshi Kishi, Takumi Yonemura
Life of this patent
Estimating the term…
Abstract
A method for manufacturing an epitaxial substrate includes the steps of: epitaxially growing a group III nitride semiconductor layer on a substrate; removing the substrate from a growth furnace; irradiating a surface of the group III nitride semiconductor layer with ultraviolet light while exposing the surface to an atmosphere containing oxygen; and measuring a sheet resistance value of the group III nitride semiconductor layer.
Claims7
A method for manufacturing an epitaxial substrate, comprising:
- epitaxially growing a group III nitride semiconductor layer on a substrate;
- removing the substrate from a growth furnace;
- irradiating a surface of the group III nitride semiconductor layer with He—Cd laser light having a center wavelength of 325 nm±5 nm while exposing the surface to an atmosphere containing oxygen, thereby promoting oxidation of surface Ga to form a Ga oxide layer having a GaO to GaN intensity ratio (IGao/IGaN) of 0.15 or more, as determined, after the irradiating, by fitting a Gaussian function to a Ga 3d peak obtained by X-ray photoelectron spectroscopy;
- and
- measuring a sheet resistance value of the group III nitride semiconductor layer,
- wherein the sheet resistance value is measured within 0.2 hours after the substrate is removed from the growth furnace,
- wherein an irradiation energy density of the He—Cd laser light is 2.4 W·s/m2 or more, and
- wherein the surface of the group Ill nitride semiconductor layer contains Ga.
A method for manufacturing an epitaxial substrate, comprising:
- epitaxially growing a group III nitride semiconductor layer on a substrate;
- removing the substrate from a growth furnace;
- irradiating a surface of the group III nitride semiconductor layer with ultraviolet light while exposing the surface to an atmosphere containing oxygen, wherein the ultraviolet light irradiation promotes oxidation of surface Ga to form a Ga oxide layer having a GaO to GaN intensity ratio (IGao/IGaN) of 0.15 or more, as determined by fitting a Gaussian function to a Ga 3d peak obtained by X-ray photoelectron spectroscopy;
- and
- measuring a sheet resistance value of the group III nitride semiconductor layer,
- wherein the sheet resistance value is measured within 0.2 hours after the substrate is removed from the growth furnace, and
- wherein the surface of the group Ill nitride semiconductor layer contains Ga, and wherein the ultraviolet light has a center wavelength of 325 nm to 422 nm.
Dependencies are inferred from the claim text.