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

• US 6,987,029 B2
• Filed: 11/17/2003
• Issued: 01/17/2006
• Est. Priority Date: 07/26/1999
• Status: Expired due to Fees

• Current Assignee: National Institute of Advanced Industrial Science and Technology (Government of Japan), ROHM Co., Ltd.
• Original Assignee: National Institute of Advanced Industrial Science and Technology (Government of Japan), ROHM Co., Ltd.
• Inventors: Niki, Shigeru, Nakahara, Ken, Tanabe, Tetsuhiro, Takasu, Hidemi, Fons, Paul, Iwata, Kakuya
• Primary Examiner(s): Wilson, Allan R.
• Application Number:
  US10/713,205
• Publication Number:
  US 20040099876A1
• Time in Patent Office: 792 Days
• Field of Search: 438/22, 438 46- 47, 438/479
• US Class Current: 438/47
• 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 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 epitaxially on said silicon nitride film a semiconductor layer lamination having at least an n-type layer and a p-type layer to form a light emitting layer which is made of a ZnO based compound semiconductor.

2. The method of claim 1, 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.

3. The method of claim 1, wherein said atmosphere containing nitrogen is an atmosphere of a NH₃ gas plasma-excited by a high-frequency power source.

4. The method of claim 1, 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. The method of claim 2, wherein said controlling a temperature or a time is a higher temperature on a shorter processing time, or a lower temperature on a longer processing time, to form said silicon nitride film in a thickness of 10 nm or less.