ZnO based compound semiconductor light emitting device and method for manufacturing the same

• US 20040099876A1
• Filed: 11/17/2003
• Published: 05/27/2004
• Est. Priority Date: 07/26/1999
• Status: Active Grant

• Current Assignee: National Institute of Advanced Industrial Science and Technology (Government of Japan)
• Original Assignee: National Institute of Advanced Industrial Science and Technology (Government of Japan)
• Inventors: Tanabe, Tetsuhiro, Niki, Shigeru, Nakahara, Ken, Takasu, Hidemi, Fons, Paul, Iwata, Kakuya
• Granted Patent: US 6,987,029 B2
• Time in Patent Office: Days
• US Class Current: 257/102
• CPC Class Codes: H01L 33/0087 with a substrate not being a II-VI compound
• CPC Class Codes: H01L 33/28 containing only elements of Group II and Group VI of the Periodic Table
• CPC Class Codes: H01S 5/021 Silicon based substrates
• CPC Class Codes: H01S 5/32308 emitting light at a wavelength less than 900 nm
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP
• CPC Class Codes: H01S 5/327 in AIIBVI compounds, e.g. ZnCdSe-laser

Abstract

A light emitting device includes a silicon substrate (1), a silicon nitride film (2) formed on the surface of the silicon substrate (1), at least an n-type layer (3), (4) and a p-type layer (6), (7) which are formed on the silicon nitride film (2) and also which are made of a ZnO based compound semiconductor, and a semiconductor layer lamination (11) in which layers are laminated to form a light emitting layer. Preferably this silicon nitride film (2) is formed by thermal treatment conducted in an atmosphere containing nitrogen such as an ammonium gas. Also, in another embodiment, a light emitting device is formed by growing a ZnO based compound semiconductor layer on a main face of a sapphire substrate, the main face being perpendicular to the C-face thereof. As a result, it is possible to obtain a device using a ZnO based compound with high properties such as an LED very excellent in crystallinity and having a high light emitting efficiency.

Claims

1. A ZnO based compound semiconductor light emitting device comprising:

a silicon substrate;

a silicon nitride film formed on the surface of said silicon substrate; and

a semiconductor layer lamination in which layers are laminated to form a light emitting layer, said layers having at least an n-type layer and a p-type layer which are formed on said silicon nitride film and also which are made of a ZnO based compound semiconductor.

2. The semiconductor light emitting device of claim 1, wherein the surface of said silicon nitride film is not made amorphous but is formed to be flat face.

3. The semiconductor light emitting device of claim 1 or 2, wherein said silicon nitride film is formed to a thickness of 10 nm or less.

4. The semiconductor light emitting device of claim 1, 2, or 3, wherein said semiconductor layer lamination has a double-hetero construction in which an active layer made of Cd_xZn_1-xO (0≦

x<

1) is sandwiched by clad layers which are made of Mg_yZn_1-yO (0≦

y<

1) and also which have a band gap energy larger than that of said active layer.

5. A method for manufacturing a semiconductor light emitting device comprising the steps of:

forming a silicon nitride film on a surface of a silicon substrate by conducting heat treatment said silicon substrate in an atmosphere containing nitrogen; and

growing on said silicon nitride film a semiconductor layer lamination to form a light emitting layer which is made of a ZnO based compound semiconductor.

6. The method of claim 5, wherein the step of forming said silicon nitride film is conducted by controlling a temperature or a time thereof so that the surface of said silicon nitride film can maintain the flat face of said silicon substrate.

7. A device having a ZnO based compound layer, comprising:

a sapphire substrate having a main face that is perpendicular to a C-face thereof; and

a ZnO based compound layer which is epitaxially grown on said main face of said sapphire substrate.

8. The device of claim 7, wherein said main face of said sapphire substrate is an A-face.

9. A method for growing a ZnO based compound crystal layer, wherein a ZnO based compound layer is grown epitaxially on a sapphire substrate so that a c-axis of said ZnO based compound layer may be perpendicular to a c-axis of said sapphire substrate.

10. A ZnO based compound semiconductor light emitting device comprising:

a sapphire substrate having a main face that is perpendicular to a C-face thereof; and

a semiconductor layer lamination in which layers are laminated to form a light emitting layer, said layers having at least an n-type layer and a p-type layer which are made of a ZnO based compound semiconductor grown epitaxially on said main face of said sapphire substrate.

11. The semiconductor light emitting device of claim 10, wherein said main face of said sapphire substrate is an A-face.

12. The semiconductor light emitting device of claim 10 or 11, wherein said semiconductor layer lamination has a double-hetero construction in which an active layer made of Cd_xZn_1-xO (0≦

x<

1) is sandwiched by clad layers which are made of Mg_yZn_1-yO (0≦

y<

±

1) and also which has a band gap energy larger than that of said active layer.