Semiconductor light-emitting device and method for fabricating the device

• US 6,794,687 B1
• Filed: 08/25/2000
• Issued: 09/21/2004
• Est. Priority Date: 08/25/1999
• Status: Expired due to Term

• Current Assignee: Xiamen San'An Optoelectronics Co.Ltd. (Sanan Optoelectronics Company Limited)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Nakatsu, Hiroshi, Kurahashi, Takahisa, Murakami, Tetsurou, Hosoba, Hiroyuki
• Primary Examiner(s): BAUMEISTER, BRADLEY W
• Application Number:
  US09/645,571
• Time in Patent Office: 1,488 Days
• Field of Search: 257/98, 257/95, 372/102
• US Class Current: 257/98
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 2933/0083 Periodic patterns for optical field-shaping in or on the semiconductor body or semiconductor body package, e.g. photonic bandgap structures
• CPC Class Codes: H01L 33/105 with a resonant cavity structure
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/38 with a particular shape

Abstract

An n-type AlAs/n-type Al_0.5Ga_0.5As DBR layer and a p-type (Al_0.2Ga_0.8)_0.5In_0.5P/p-type Al_0.5In_0.5P DBR layer are formed on an n-type GaAs substrate at specified intervals so that a reflection spectrum is centered at 650 nm and the resonance wavelength becomes 650 nm. A quantum well active layer (light-emitting layer) is formed so that the light emission peak wavelength becomes 650 nm in the belly position of the standing wave generated in a resonator constructed of both the DBR layers. A grating pattern is formed on the surface of a p-type Al_0.5Ga_0.5As light diffusion layer that serves as a light-emitting surface surrounded by a p-type electrode. By thus roughening the light-emitting surface, light emitted from the light-emitting layer is diffused in various directions, reducing the radiation angle dependency of the emission light wavelength.

Claims

1. A semiconductor light-emitting device comprising:

a resonator including multi-layer reflection films on a GaAs substrate side and a surface side that are formed with interposition of an interval in a direction perpendicular to the GaAs substrate on the GaAs substrate,

a light-emitting layer formed in an anti-node position of a standing wave between the multi-layer reflection films, and

a semiconductor layer which has one or more layers and an uppermost diffusion layer whose surface comprises roughened means for light diffusing which causes light output from the device to be diffused upon leaving said surface of said uppermost diffusion layer, the semiconductor layer being formed on the multi-layer reflection film located on the opposite side of the GaAs substrate with respect to the light-emitting layer.

2. A semiconductor light-emitting device as claimed in claim 1, wherein

the light-emitting layer is constructed of an Al_yGa_zIn<sub>1− y−

z</sub>P (0≦

y≦

1, 0≦

z≦

1) layer comprised of a single layer or a plurality of layers.

3. A semiconductor light-emitting device as claimed in claim 1, wherein

the multi-layer reflection film located on the GaAs substrate side with respect to the light-emitting layer is an Al_xGa₁₋

xAs (0≦

x≦

1) layer, and

the multi-layer reflection film located on the opposite side of the GaAs substrate with respect to the light-emitting layer is constructed of an Al_yGa_zIn<sub>1−

y−

z</sub>P (0≦

y≦

1, 0≦

z≦

1) layer.

4. The semiconductor light-emitting device of claim 1, wherein the diffusion layer comprises a light diffusion layer.

5. The semiconductor light-emitting device of claim 1, wherein the diffusion layer comprises a current diffusion layer.

6. A semiconductor light-emitting device comprising:

a resonator including a pair of multi-layer reflection films formed with interposition of an interval on a GaAs inclusive substrate,

a light-emitting layer located between the multi-layer reflection films,

a semiconductor layer which has one or more layers and an uppermost diffusion layer whose surface is roughened in a light diffusing manner so as to cause light output from the device to be diffused upon leaving said surface of the uppermost diffusion layer, the semiconductor layer being formed on the multi-layer reflection film located on the opposite side of the GaAs substrate with respect to the light-emitting layer, and

wherein at least a portion of the roughened surface of the semiconductor layer is exposed so that it is not contacted by any metal film.

7. The semiconductor light-emitting device of claim 6, wherein the diffusion layer comprises a light diffusion layer.

8. The semiconductor light-emitting device of claim 6, wherein the diffusion layer comprises a current diffusion layer.

9. A light emitting device comprising:

a semiconductor substrate;

a resonator including first and second multi-layered reflectors supported by the substrate;

a light emitting layer provided between the first and second multi-layered reflectors;

a semiconductor diffusion layer supported by the substrate, with the reflectors being provided between the substrate and the semiconductor layer, the semiconductor diffusion layer including an uppermost surface which includes a roughened means for causing light output from the device to be diffused upon leaving said roughened means at said uppermost surface of the semiconductor diffusion layer;

a dielectric layer provided on the substrate over the semiconductor layer; and

an aperture provided in the dielectric layer, the aperture being located over at least part of the roughened means portion of the semiconductor layer.

10. The device of claim 9, wherein the dielectric layer comprises silicon oxide.

11. The device of claim 9, wherein the roughened means of the semiconductor layer is exposed in the aperture of the dielectric layer, and no metal layer is provided over and contacting at least a portion of the roughened means of the semiconductor layer in the aperture.