Method of producing microstructure of nitride semiconductor and photonic crystal prepared according to the method

Patent metadata

Field	Value
Publication number	US-9437684-B2
Application number	US-201414336978-A
Country	US
Kind code	B2
Filing date	Jul 21, 2014
Priority date	Jul 30, 2009
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

The method of producing a GaN-based microstructure includes a step of preparing a semiconductor structure provided with a trench formed in a main surface of the nitride semiconductor and a heat-treating mask covering a main surface of the nitride semiconductor excluding the trench, a first heat-treatment step of heat-treating the semiconductor structure under an atmosphere containing nitrogen element to form a crystallographic face of the nitride semiconductor on at least a part of a sidewall of the trench, a step of removing the heat-treating mask after the first heat-treatment step and a second heat-treatment step of heat-treating the semiconductor structure under an atmosphere containing nitrogen element to close an upper portion of the trench on the sidewall of which the crystallographic face is formed with a nitride semiconductor.

First claim

The invention claimed is:

1. A structure comprising a substrate and a semiconductor layer including a nitride semiconductor,
wherein a hole is formed in the semiconductor layer,
wherein the hole comprises a first portion having a substantial prism shape formed of a plurality of faces substantially perpendicular to an in-plane direction of the substrate and a second portion adjacently connected to the first portion and having a pyramid or truncated pyramid shape formed of a plurality of faces being not perpendicular to the in-plane direction of the substrate and inclined with respect to the in-plane direction of the substrate, and
wherein a crystallographic face of the nitride semiconductor is formed on at least a part of the plurality of faces constituting the first portion of the hole and at least a part of the plurality of faces constituting the second portion of the hole.

2. The structure according to claim 1 , wherein the substantial prism shape of the first portion of the hole comprises a hexagonal column and the pyramid shape of the second portion of the hole comprises a hexagonal cone.

3. The structure according to claim 1 , wherein the substantial prism shape of the first portion of the hole comprises a hexagonal column and the pyramid shape of the second portion of the hole comprises an octahedron.

4. The structure according to claim 1 , wherein a separation of opposite sidewall surfaces of the hole is 1 μm or less.

5. The structure according to claim 1 , wherein an aspect ratio of the hole is 2 or more.

6. The structure according to claim 1 , wherein a diameter of the hole is 300 nm or less, and an aspect ratio of the hole is 2 or less.

7. The structure according to claim 1 , wherein a diameter of the hole is 150 nm or less.

8. The structure according to claim 1 , wherein the semiconductor layer comprises a first nitride semiconductor layer and a second nitride semiconductor layer.

9. The structure according to claim 1 , wherein the semiconductor layer includes at least one of a group III element.

10. The structure according to claim 1 , wherein the semiconductor layer includes at least one of GaN, AlN, AlGaN, InGaN and InN.

11. The structure according to claim 1 , wherein the hole is closed by the nitride semiconductor.

12. A surface-emitting laser comprising the structure according to claim 1 and an active layer.

13. The structure according to claim 1 , wherein a first crystallographic face of the nitride semiconductor is formed on the at least a part of the plurality of faces constituting the first portion of the hole and a second crystallographic face of the nitride semiconductor is formed on the at least a part of the plurality of faces constituting the second portion of the hole.

14. The structure according to claim 13 , wherein a crystallographic pattern of the first crystallographic face is different from a crystallographic pattern of the second crystallographic face.

15. The structure according to claim 13 , wherein the first crystallographic face is a surface equivalent to either of a (0001) surface or a (1-10n (wherein, n is an integer of 0 to 4)) surface.

16. The structure according to claim 15 , wherein the second crystallographic face is a surface equivalent to either of a (0001) surface or a (1-10n (wherein, n is an integer of 0 to 4)) surface.

Assignees

• Canon Kk

Inventors

• Kawashima Shoichi
• Kawashima Takeshi
• Nagatomo Yasuhiro
• Hoshino Katsuyuki

Classifications

• H10P14/3802

  Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth · CPC title

• H10P14/3416

  Nitrides · CPC title

• H10P14/3258

  Crystal orientation · CPC title

• H10P14/3256

  Microstructure · CPC title

• H10P14/3216

  Nitrides · CPC title