Optical semiconductor device

• US 6,785,311 B1
• Filed: 08/27/2001
• Issued: 08/31/2004
• Est. Priority Date: 12/15/1998
• Status: Expired due to Fees

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Najda, Stephen Peter
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): FORDE, DELMA ROSA
• Application Number:
  US09/857,936
• Time in Patent Office: 1,100 Days
• Field of Search: 372/43-50, 257/18, 257/96, 257/15, 257/17, 257/22, 257/92, 257/184, 257/190, 257/13
• US Class Current: 372/45.01
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 5/20 Structure or shape of the semiconductor body to guide the optical wave ; Confining structures perpendicular to the optical axis, e.g. index or gain guiding, stripe geometry, broad area lasers, gain tailoring, transverse or lateral reflectors, special cladding structures, MQW barrier reflection layers
• CPC Class Codes: H01S 5/2004 Confining in the direction perpendicular to the layer structure
• CPC Class Codes: H01S 5/2009 by using electron barrier layers
• CPC Class Codes: H01S 5/2013 MQW barrier reflection layers
• CPC Class Codes: H01S 5/3415 containing details related to carrier capture times into wells or barriers

Abstract

An optical semiconductor device comprising: an active region; and a p-doped cladding region disposed on one side of the active region; wherein an electron-reflecting barrier is provided on the p-side of the active region for reflecting both Γ-electrons and X-electrons, the electron-reflecting barrier providing a greater potential barrier to Γ-electrons than the p-doped cladding region.

Claims

1. An optical semiconductor device comprising:

an active region; and

a p-doped cladding region disposed on one side of the active region;

wherein an electron-reflecting barrier is provided between the cladding region and the active region for reflecting both Γ

-electrons and X-electrons, the electron-reflecting barrier providing a greater potential barrier to Γ

-electrons than the p-doped cladding region,

wherein the electron-reflecting barrier comprises a first electron-reflecting layer for reflecting Γ

-electrons and a second electron-reflecting layer for reflecting X-electrons.

2. A device according to claim 1, wherein at least one of the electron-reflecting layers is a strained layer.

3. A device according to claim 2, wherein one of the electron-reflecting layers is in a state of compressive strain and the other of the electron-reflecting layers is in a state tensile strain.

4. A device according to claim 1, wherein the device is a light-emitting diode.

5. A device according to claim 1, wherein the device is a laser device.

6. A device according to claim 5, wherein the device is a separate confinement heterostructure laser device comprising an optical guiding region, the active region being disposed within the optical guiding region.

7. A device according to claim 1, wherein the layer for reflecting Γ

-electrons is disposed between the optical guiding region and the layer for reflecting x-electrons.

8. A device according to claim 7, wherein the Γ

-conduction band of the optical guiding region is substantially degenerate with the x-conduction band of the layer for reflecting Γ

-electrons.

9. A device according to claim 1, wherein the layer for reflecting Γ

-electrons is disposed between the layer for reflecting x-electrons and the p-doped cladding region.

10. A device according to claim 1, wherein the electron-reflecting barrier comprises a plurality of first electron-reflecting layers for reflecting Γ

-electrons and a plurality of second electron-reflecting layers for reflecting x-electrons.

11. A device according to claim 10, wherein the electron-reflecting barrier is a superlattice structure.

12. A device according to claim 1, wherein the device is fabricated in the (Al, Ga, In)P system, the layer for reflecting Γ

-electrons is made from a material selected from the group consisting of AlP and GaP, and the layer for reflecting x-electrons is made from InP.

13. A device according to claim 10, wherein the device is fabricated in the (Al Ga, In)P system, each layer for reflecting Γ

-electrons is made of a material selected from the group consisting of AlP and GaP, and the layer for reflecting x-electrons is made from InP.

14. A device according to claim 8, wherein the layer for reflecting Γ

-electrons is AlP and the optical guiding region is (Al_0.3Ga_0.7)_0.52In_0.48P.

15. A device according to claim 12, wherein the thickness of each of the electron-reflecting layers is 16Å

or less.

16. A device according to claim 1, wherein at least one of the electron-reflecting layers is p-doped.

17. A device according to claim 12, wherein the first electron-reflecting layer contains indium.

18. A device according to claim 6, wherein the electron-reflecting barrier is disposed between the optical guiding region and the p-doped cladding region.

19. An optical semiconductor device comprising:

an optical guiding region;

an active region having at least one energy well, said active region being disposed in said optical guiding region; and

n-doped and p-doped cladding regions disposed on opposite sides of the optical guiding region;

wherein an electron-reflecting layer for reflecting Γ

-electrons is provided between the p-doped cladding region and the active region; and

wherein the electron-reflecting layer contacts with the optical guiding region so that the Γ

-conduction band of the optical guiding region is substantially degenerate with the X-conduction band of the electron-reflecting layer, and

the electron-reflecting layer is formed of AlP.

20. A device according to claim 19, wherein the optical guiding region is formed of (Al_0.5Ga_0.7)_0.52In_0.48P.

21. A device according to claim 19, wherein the electron-reflecting layer is p-doped.

22. A device according to claim 19, wherein the electron-reflecting layer is disposed between the optical guiding region and the p-doped cladding region.

23. A device according to claim 19, wherein the device is a separate confinement heterostructure laser device.