Light receiving element, semiconductor epitaxial wafer, method for manufacturing the light receiving element, method for manufacturing the semiconductor epitaxial wafer, and detecting device

Patent metadata

Field	Value
Publication number	US-9312422-B2
Application number	US-201113991129-A
Country	US
Kind code	B2
Filing date	Nov 29, 2011
Priority date	Dec 1, 2010
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

A light receiving element includes an InP substrate that is transparent to light having a wavelength of 3 to 12 μm, a buffer layer located in contact with the InP substrate, and a light-receiving layer having a multiple quantum well structure, the light-receiving layer having a cutoff wavelength of 3 μm or more and being lattice-matched with the buffer layer. In the light receiving element, the buffer layer is epitaxially grown on the InP substrate while the buffer layer and the InP substrate exceed a range of a normal lattice-matching condition, and the buffer layer is constituted by a GaSb layer.

First claim

The invention claimed is:

1. A light receiving element formed by using a group III-V compound semiconductor, the light receiving element comprising:
an InP substrate that is transparent to light having a wavelength of 3 to 12 μm;
a buffer layer having a thickness of 2 μm or more and located in contact with the InP substrate; and
a light-receiving layer having a multiple quantum well structure and located in contact with the buffer layer,
wherein the light-receiving layer has a cutoff wavelength of 3 μm or more and is lattice-matched with the buffer layer,
the buffer layer is epitaxially grown on the InP substrate while a value |a 2 −a 1 |/a 1 exceeds a range of a normal lattice-matching condition, where a 2 represents a lattice parameter of the buffer layer and a 1 represents a lattice parameter of the InP substrate,
the buffer layer is constituted by a GaSb layer doped with Te, and the buffer layer has a carrier concentration of 1E18 cm −3 or more, and
the light receiving element has a structure in which light is incident from a rear surface of the InP substrate.

2. The light receiving element according to claim 1 , wherein the InP substrate that is transparent to light having a wavelength of 3 to 12 μm is an InP substrate to which sulfur (S) is not added.

3. The light receiving element according to claim 1 , wherein the InP substrate that is transparent to light having a wavelength of 3 to 12 μm is an Fe-containing InP substrate or an undoped InP substrate.

4. The light receiving element according to claim 1 , wherein the light-receiving layer has a p-n junction therein.

5. The light receiving element according to claim 1 , wherein the light-receiving layer includes an insertion layer that is composed of a group III-V compound semiconductor and that is lattice-matched with the light-receiving layer, and a insertion layer conduction band bottom is higher than a light-receiving layer conduction band bottom.

6. The light receiving element according to claim 1 , wherein the multiple quantum well structure is a type-II multiple quantum well structure selected from {(InAs/GaSb), (InAs/InGaSb), (InAsSb/GaSb), and (InAsSb/InGaSb)}.

7. A detecting device comprising the light receiving element according to claim 1 ; and a read-out integrated circuit (ROIC), wherein a pixel electrode in the light receiving element is connected to a read-out electrode in the ROIC with a bump interposed therebetween.

8. The light receiving element according to claim 1 , wherein the buffer layer consists essentially of GaSb.

9. A semiconductor epitaxial wafer formed by using a group III-V compound semiconductor, the semiconductor epitaxial wafer comprising:
an InP substrate that is transparent to light having a wavelength of 3 to 12 μm; and
a buffer layer having a thickness of 2 μm or more and located in contact with the InP substrate,
wherein a value of |a 2 −a 1 |/a 1 exceeds a range of a normal lattice-matching condition, where a 2 represents a lattice parameter of the buffer layer and a 1 represents a lattice parameter of the InP substrate, and
the buffer layer is constituted by a GaSb layer doped with Te, and the buffer layer has a carrier concentration of 1E18 cm −3 or more.

10. The semiconductor epitaxial wafer according to claim 9 , wherein the InP substrate that is transparent to light having a wavelength of 3 to 12 μm is an Fe-containing InP substrate or an undoped InP substrate.

11. The semiconductor epitaxial wafer according to claim 9 , further comprising a first semiconductor layer including a multiple quantum well structure, the first semiconductor layer being lattice-matched with the buffer layer.

12. The semiconductor epitaxial wafer according to claim 11 , wherein the multiple quantum well structure is a type-II multiple quantum well structure selected from {(InAs/GaSb), (InAs/InGaSb), (InAsSb/GaSb), and (InAsSb/InGaSb)}.

13. The semiconductor epitaxial wafer according to claim 9 , wherein the buffer layer consists essentially of GaSb.

Assignees

• Miura Kohei
• Inada Hiroshi
• Iguchi Yasuhiro
• Saito Tadashi
• Sumitomo Electric Industries

Inventors

• Miura Kohei
• Inada Hiroshi
• Iguchi Yasuhiro
• Saito Tadashi

Classifications

• H10P14/3422

  Antimonides · CPC title

• H10P14/3421

  Arsenides · CPC title

• H10P14/3251

  consisting of three or more layers · CPC title

• H10P14/3222

  Antimonides · CPC title

• H10P14/3221

  Arsenides · CPC title