Semiconductor light emitting element

• US 6,797,986 B1
• Filed: 06/30/2000
• Issued: 09/28/2004
• Est. Priority Date: 08/24/1999
• 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: Hosoba, Hiroyuki, Nakatsu, Hiroshi, Kurahashi, Takahisa, Murakami, Tetsurou
• Primary Examiner(s): Kang, Donghee
• Application Number:
  US09/607,965
• Time in Patent Office: 1,551 Days
• Field of Search: 257/94-99, 257/79, 257/83, 257/93, 257/103, 372/45, 372/46
• US Class Current: 257/98
• CPC Class Codes: H01L 33/105 with a resonant cavity structure
• CPC Class Codes: H01L 33/30 containing only elements of Group III and Group V of the Periodic Table
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/42 Transparent materials
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector

Abstract

Is provided a resonant cavity type light emitting diode having excellent humidity durability and a light output unsaturated even several 10 mA., which is suitable for mass production. The semiconductor light emitting element has a resonator formed by one set of multi-layer reflecting films disposed at a constant distance on a GaAs substrate inclined at an angle of not less than 2 degrees in the direction [011] or [0-1-1] from the plane (100) and a light emitting layer disposed at a loop position of a standing wave in the resonator, wherein a multi-layer reflecting film disposed on the GaAs substrate side is composed of plural layers of Al_xGa_1-xAs (0 ≦x≦1) and a multi-layer reflecting film disposed on the opposite side of the GaAs substrate is composed of plural layers of Al_yGa_zIn_1-y-zP (0≦y≦1, 0≦z≦1), thereby achieving an improved humidity durability and an increased reflection factor by increasing the number of the reflection layers.

Claims

1. A semiconductor light emitting element having a resonator composed of paired multi-layer reflecting films disposed at a constant distance on a GaAs substrate and having a light emitting layer disposed at a loop position of a standing wave in the resonator, wherein a multi-layer reflecting film on the GaAs substrate side of the light emitting layer comprises plural layers of Al_xGa_1-xAs (0≦

x≦

1) and a multi-layer reflecting film on the other side of the light emitting layer comprises plural layers of Al_yGa_zIn_1-y-zP (0≦

y≦

1, 0≦

z≦

1).

2. A semiconductor light emitting element as defined in claim 1, wherein the light emitting layer comprises a single- or multi-layer film of Al_yGa_zIn_1-y-zP (0≦

y≦

1, 0≦

z≦

1).

3. A semiconductor light emitting element as defined in claim 1 or 2, wherein a current constricting structure of an insulation layer is disposed above the light emitting layer.

4. A semiconductor light emitting element as defined in claim 3, wherein a current diffusion layer is formed above the layer forming the current constricting structure.

5. A semiconductor light emitting element as defined in claim 4, wherein the current diffusion layer is formed by a transparent electrode having the transmittance of the emitted light, which transmittance is not less than 50%.

6. A semiconductor light emitting element as defined in claim 1 or 2, wherein a current constricting structure of the same conductive type as the GaAs substrate is disposed above the light emitting layer.

7. A semiconductor light emitting element as defined in claim 6, wherein the current constricting structure is formed by a layer of Al_xGa_1-xAs (0≦

x≦

1).

8. A semiconductor light emitting element as defined in claim 7, wherein a current diffusion layer is formed by a layer of Al_xGa_1-xAs (0≦

x≦

1).

9. A semiconductor light emitting element as defined in claim 7, wherein a current diffusion layer is formed above the layer forming the current constricting structure.

10. A semiconductor light emitting element as defined in claim 9, wherein the current diffusion layer is formed by a layer of Al_yGa_zIn_1-y-zP (0≦

y≦

1, 0≦

z≦

1).

11. A semiconductor light emitting element as defined in claim 6, wherein the current constricting structure is formed by a layer of Al_yGa_zIn_1-y-zP (0≦

y≦

1, 0≦

z≦

1).

12. A semiconductor light emitting element as defined in claim 11, wherein a current diffusion layer is formed above the layer forming the current constricting structure.

13. A semiconductor light emitting element as defined in claim 12, wherein the current diffusion layer is formed by a layer of Al_yGa_zIn_1-y-zP (0≦

y≦

1, 0≦

z≦

1).

14. A semiconductor light emitting element as defined in claim 11, wherein a current diffusion layer is formed by a layer of Al_xGa_1-xAs (0≦

x≦

1).

15. A semiconductor light emitting element as defined in claim 6, wherein a current diffusion layer is formed above the layer forming the current constricting structure.

16. A semiconductor light emitting element as defined in claim 15, wherein the current diffusion layer is formed by a transparent electrode having the transmittance of the emitted light, which transmittance is not less than 50%.

17. A semiconductor light emitting element as defined in claim 15, wherein the current diffusion layer is formed by a layer of Al_yGa_zIn_1-y-zP (0≦

y≦

1, 0≦

z≦

1).

18. A semiconductor light emitting element as defined in claim 15, wherein the current diffusion layer is formed by a layer of Al_xGa_1-xAs (0≦

x≦

1).

19. A semiconductor light emitting element as defined in claim 1, wherein the GaAs substrate has a surface inclined at an angle of not less than 2 degrees in the direction [0 1 1] or [0-1-1] from the plane (100).

20. A semiconductor light emitting element, comprising:

a substrate;

a light emitting layer; and

a resonator comprising first and second reflecting films disposed on opposite sides of the light emitting layer, wherein the first reflecting film comprises Al_xGa_1-xAs (0≦

x≦

1) and the second reflecting film comprises Al_yGa_zIn_1-y-zP (0≦

y≦

1, 0≦

z≦

1),

wherein the first reflecting film is disposed on the same side of the light emitting laver as the substrate.

21. A semiconductor light emitting element as defined in claim 20, wherein the light emitting layer comprises one or more films of Al_yGa_zIn_1-y-zP (0≦

y≦

1, 0≦

z≦

1).

22. A semiconductor light emitting element as defined in claim 20, further comprising:

a current constricting layer provided on the side of the light emitting layer opposite the side on which the substrate is provided.

23. A semiconductor light emitting element as defined in claim 22, wherein the current constricting layer comprises an insulating layer.

24. A semiconductor light emitting element as defined in claim 22, wherein the current constricting layer comprises material of the same conductive type as the substrate.

25. A semiconductor light emitting element as defined in claim 22, further comprising:

a current diffusion layer formed on the current constricting layer.

26. A semiconductor light emitting element as defined in claim 25, wherein the current diffusion layer comprises Al_yGa_zIn_1-y-zP (0≦

y≦

1, 0≦

z≦

1).

27. A semiconductor light emitting element as defined in claim 20, wherein the substrate comprises a GaAs substrate having a surface inclined at not less than 2 degrees in the direction [011] or [0-1-1] from the plane (100).

28. A semiconductor light emitting element as defined in claim 20, wherein the resonator has a resonant wavelength of 650 nm.

29. A semiconductor light emitting element as defined in claim 20, wherein the length of the resonator is 1.5 times the resonant wavelength of the resonator.