Diamond substrate and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-11753740-B2
Application number	US-202017099229-A
Country	US
Kind code	B2
Filing date	Nov 16, 2020
Priority date	Nov 18, 2019
Publication date	Sep 12, 2023
Grant date	Sep 12, 2023

Abstract

A method for manufacturing diamond substrate of using source gas containing hydrocarbon gas and hydrogen gas to form diamond crystal on an underlying substrate by CVD method, to form a diamond crystal layer having nitrogen-vacancy centers in at least part of the diamond crystal, nitrogen or nitride gas is mixed in the source gas, wherein the source gas is: 0.005 volume % or more and 6.000 volume % or less of the hydrocarbon gas; 93.500 volume % or more and less than 99.995 volume % of the hydrogen gas; and 5.0×10 −5 volume % or more and 5.0×10 −1 volume % or less of the nitrogen gas or the nitride gas, and the diamond crystal layer having the nitrogen-vacancy centers is formed. A method for manufacturing a diamond substrate to form an underlying substrate, a diamond crystal having a dense nitrogen-vacancy centers (NVCs) with an orientation of NV axis by performing the CVD.

First claim

The invention claimed is:

1. A diamond substrate comprising a diamond crystal layer having nitrogen-vacancy centers and no silicon-vacancy centers, wherein a light intensity I NV− of an NV − center light (wavelength: 637 nm) is I NV− ≥2800 counts when the diamond crystal layer having the nitrogen-vacancy centers and no silicon-vacancy centers is measured by a photoluminescence apparatus under conditions:
an excitation light wavelength of 532 nm;
an excitation light intensity of 2.0 mW;
a total time of 1 second; a total number of 3 times;
a hole diameter of 100 μm;
an objective lens with a magnification of 15; and
measurement in room temperature of 298 K.

2. The diamond substrate according to claim 1 , wherein a ratio I NV− /IRaman of a light intensity I NV− of an NV − center light (wavelength: 637 nm) and a light intensity IRaman of a Raman scattered light (wavelength: 573 nm) is I NV− /IRaman≥0.04 when the diamond crystal layer having the nitrogen-vacancy centers and no silicon-vacancy centers is measured by the photoluminescence apparatus under conditions:
an excitation light wavelength of 532 nm;
an excitation light intensity of 2.0 mW;
a total time of 1 second;
a total number of 3 times;
a hole diameter of 100 μm;
an objective lens with a magnification of 15; and
measurement in room temperature of 298 K.

3. The diamond substrate according to claim 1 , wherein a nitrogen concentration [N] in the diamond crystal layer having the nitrogen-vacancy centers and no silicon-vacancy centers is 5×10 17 atoms/cm 3 ≤[N]≤9×10 19 atoms/cm 3 .

4. The diamond substrate according to claim 1 , wherein an average surface roughness Ra of a surface of the diamond crystal layer having the nitrogen-vacancy centers and no silicon-vacancy centers is Ra≤270 nm.

Assignees

• Shinetsu Chemical Co
• Univ Nat Corp Kanazawa

Inventors

• Noguchi Hitoshi
• Tokuda Norio
• Matsumoto Tsubasa

Classifications

• C23C16/277 Primary

  using other elements in the gas phase besides carbon and hydrogen; using other elements besides carbon, hydrogen and oxygen in case of use of combustion torches; using other elements besides carbon, hydrogen and inert gas in case of use of plasma jets · CPC title

• C30B29/04 Primary

  Diamond · CPC title

• C23C16/278

  doping or introduction of a secondary phase in the diamond · CPC title

• C30B25/02

  Epitaxial-layer growth · CPC title

• C30B25/18

  characterised by the substrate · CPC title