Semiconductor light-emitting element and method of manufacturing the same

• US 6,528,823 B2
• Filed: 09/24/2001
• Issued: 03/04/2003
• Est. Priority Date: 09/28/2000
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Akaike, Yasuhiko, Furukawa, Kazuyoshi
• Primary Examiner(s): Zarabian, Amir
• Assistant Examiner(s): Soward, Ida M.
• Application Number:
  US09/961,177
• Publication Number:
  US 20020036296A1
• Time in Patent Office: 526 Days
• Field of Search: 257/94-97, 257/79, 257/12-13, 257/103, 257/184, 257/201
• US Class Current: 257/79
• CPC Class Codes: H01L 33/305 characterised by the doping materials

Abstract

A semiconductor light-emitting element, including a double hetero structure formed of III-V group compound semiconductor layers including an active layer acting as a light emitting layer and an n-type cladding layer and a p-type cladding layer having the active layer sandwiched therebetween, a p-type layer laminated on the double hetero structure and containing a concentration of Zn as a dopant, and a Zn diffusion preventing layer interposed between the active layer of the double hetero structure and the p-type layer having a high Zn concentration.

Claims

1. A semiconductor light-emitting element, comprising:

a double hetero structure formed of III-V group compound semiconductor layers including an active layer acting as a light emitting layer and an n-type cladding layer and a p-type cladding layer having the active layer sandwiched therebetween;

a p-type layer laminated on said double hetero structure and containing a concentration of Zn as a dopant; and

a Zn diffusion preventing layer interposed between said double hetero structure and the p-type layer.

2. The semiconductor light-emitting element according to claim 1, wherein said double hetero structure is formed of an InGaAlP series material.

3. The semiconductor light-emitting element according to claim 1, wherein said Zn diffusion preventing layer is doped with a p-type dopant of Zn and an n-type dopant of Si, and the concentrations of the Zn and Si dopants satisfy the conditions of Na>

Nd and Nd>

2×

10¹⁷ cm<sup>−

3</sup>, where Na represents the concentration of the dopant Zn, and Nd represents the concentration of the dopant Si.

4. The semiconductor light-emitting element according to claim 1, wherein said Zn diffusion preventing layer has a composition of In_0.5(Ga₁₋

xAl_x)_0.5P where x is larger than 0 and smaller than 1 (0<

x<

1).

5. A semiconductor light-emitting element, comprising:

a double hetero structure formed of III-V group compound semiconductor layers including an active layer acting as a light emitting layer and an n-type cladding layer and a p-type cladding layer having the active layer sandwiched therebetween;

a p-type substrate containing Zn as a dopant, formed of a material transparent to the light emitted from said light emitting layer, and said p-type cladding layer included in said double hetero structure being formed on said p-type substrate; and

a Zn diffusion preventing layer formed between said double hetero structure and said p-type substrate.

6. The semiconductor light-emitting element according to claim 5, wherein said double hetero structure is formed of an InGaAlP series material, and said p-type substrate is formed of a p-type GaP.

7. The semiconductor light-emitting element according to claim 5, wherein said Zn diffusion preventing layer has a composition of In_0.5(Ga₁₋

xAl_x)_0.5P where x is larger than 0 and smaller than 1 (0<

x<

1).

8. The semiconductor light-emitting element according to claim 5, wherein said Zn diffusion preventing layer is doped with a p-type dopant of Zn and an n-type dopant of Si, and the concentrations of the Zn and Si dopants satisfy the conditions of Na>

Nd and Nd>

2×

10¹⁷ cm<sup>−

3</sup>, where Na represents the concentration of the dopant Zn, and Nd represents the concentration of the dopant Si.

11. The semiconductor light-emitting element according to claim 5, wherein said p-type substrate is bonded directly to said p-type cladding layer.

9. An LED (light emitting diode), comprising:

a p-type substrate containing Zn as a dopant;

a first electrode formed on the lower surface of said substrate;

a p-type buffer layer formed on the upper surface of said substrate;

a p-type adhesive layer bonded to said buffer layer;

a Zn diffusion preventing layer formed on said adhesive layer;

a p-type cladding layer formed on said Zn diffusion preventing layer;

an active layer formed on said p-type cladding layer;

an n-type cladding layer formed on said active layer;

an electrode diffusion layer formed on said n-type cladding layer; and

a second electrode formed on said electrode diffusion layer.

10. A semiconductor laser, comprising:

a substrate;

an n-type cladding layer formed on said substrate;

an active layer formed on said n-type cladding layer;

a lower p-type cladding layer formed on said active layer;

an etching stopper layer formed on said lower p-type cladding layer;

a ridge-shaped upper p-type cladding layer formed on said etching stopper layer;

a current facilitating layer formed on said upper p-type cladding layer;

an n-type layer formed around said upper p-type cladding layer and said current facilitating layer;

a Zn diffusion preventing layer formed commonly on said current facilitating layer and said n-type layer; and

a p-type layer containing Zn as a dopant and formed on said Zn diffusion preventing layer.