Semiconductor light emitting element, display device and optical information reproduction device using the same, and fabrication method of semiconductor light emitting element

• US 6,670,647 B1
• Filed: 08/30/2000
• Issued: 12/30/2003
• Est. Priority Date: 08/31/1999
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Yamasaki, Yukio, Ito, Shigetoshi
• Primary Examiner(s): Eckert, George
• Assistant Examiner(s): NGUYEN, JOSEPH H
• Application Number:
  US09/652,101
• Time in Patent Office: 1,217 Days
• Field of Search: 257/99, 257/101, 257/102, 257/103, 257/615, 257/627, 257/14, 257/613
• US Class Current: 257/99
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G11B 7/127 Lasers; Multiple laser arrays lasers per se H01S
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01S 2301/14 Semiconductor lasers with special structural design for lasing in a specific polarisation mode
• CPC Class Codes: H01S 2304/04 MOCVD or MOVPE
• CPC Class Codes: H01S 5/0213 Sapphire, quartz or diamond based substrates
• CPC Class Codes: H01S 5/04257 having positive and negative electrodes on the same side of the substrate
• CPC Class Codes: H01S 5/1057 varying composition along the optical axis
• CPC Class Codes: H01S 5/320275 semi-polar orientation
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser

Abstract

A semiconductor light emitting element includes: a first conductive type layer made of a nitride semiconductor which is deposited on a substrate; a quantum well active layer made of Al_PGa_QIn_1−P−QN (O≦P, O≦Q, P+Q<1) which is deposited on the first conductive type layer, the quantum well active layer including a pair of barrier layers and a well layer interposed therebetween; and a second conductive type layer made of a nitride semiconductor which is deposited on the quantum well active layer, wherein light spontaneously emitted from end faces of the quantum well active layer to polarized in a direction parallel to the substrate.

Claims

1. A semiconductor light emitting element, comprising:

a first conductive type layer made of a nitride semiconductor which is deposited on a substrate;

a quantum well active layer made of Al_PGa_QIn<sub>1−

P−

Q</sub>N (0≦

P, 0≦

Q, P+Q<

1) which is deposited on the first conductive type layer, the quantum well active layer including a pair of barrier layers and a well layer interposed therebetween; and

a second conductive type layer made of a nitride semiconductor which is deposited on quantum well active layer,

wherein spontaneous emission light emitted from end faces of the quantum well active layer is polarized in a direction parallel to the substrate;

the well layer includes, in a mixed state, regions in which an in content is high and regions in which an in content is low; and

an average size of the regions in which an in content is high is 5 nm to 100 nm from larger than 5 nm up to and including 100 nm.

2. A semiconductor light emitting element according to claim 1, wherein:

the substrate is a sapphire substrate or a GaN substrate; and

the first conductive type layer is deposited on a (0001) face of the sapphire substrate or the GaN substrate.

5. A display device using the semiconductor light emitting element of claim 1.

6. An optical information reproduction device using the semiconductor light emitting element of claim 1.

7. A method for fabricating the semiconductor light emitting element of claim 1, comprising a step of growing crystal grains for the well layer,

wherein either before or after the step of growing crystal grains for the well layer, the provision of III-group material is substantially stopped for 1 to 300 seconds.

8. A semiconductor light emitting element according to claim 1, wherein the semiconductor light emitting element is a semiconductor laser element.

9. A semiconductor light emitting element according to claim 8, wherein, when a half amount of threshold current is injected, a ratio of spontaneous emission light polarized in the direction parallel to a substrate and emitted from end faces of the quantum well active layer is equal to or larger than 10.

3. A semiconductor light emitting element, comprising:

a first conductive type layer made of a nitride semiconductor which is deposited on a substrate;

a quantum well active layer made of Al_PGa_QIn<sub>1−

P−

Q</sub>N (0≦

P, 0≦

Q, P+Q<

1) which is deposited on the first conductive type layer, the quantum well active layer including a pair of barrier layers and a well layer interposed therebetween; and

a second conductive type layer made of a nitride semiconductor which is deposited on the quantum well active layer,

wherein spontaneous emission light emitted from end faces of the quantum well active layer is polarized in a direction parallel to the substrate, and

wherein;

the substrate is a sapphire substrate;

the first conductive type layer is deposited on a face tilted from a (0001) face of the sapphire substrate by an angle equal to or greater than 0.05° and

smaller than 0.20°

; and

regions of high in content and regions of low in content are provided within the active layer.

10. A semiconductor light emitting element according to claim 3, wherein:

an average size of the regions in which an in content is high is from larger than 5 nm up to and including 100 nm.

12. A semiconductor light emitting element according to claim 10, wherein the semiconductor light emitting element is a semiconductor laser element.

13. A semiconductor light emitting element according to claim 12, wherein, when a half amount of threshold current is injected, a ratio of spontaneous emission light polarized in the direction parallel to the substrate and emitted from end faces of the quantum well active layer is equal to or larger than 10.

4. A semiconductor light emitting element, comprising:

a first conductive type layer made of a nitride semiconductor which is deposited on a substrate;

a quantum well active layer made of Al_PGa_QIn<sub>1−

P−

Q</sub>N (0≦

P, 0≦

Q, P+Q<

1) which is deposited on the first conductive type layer, the quantum well active layer including a pair of barrier layers and a well layer interposed therebetween; and

a second conductive type layer made of a nitride semiconductor which is deposited on quantum well active layer,

wherein spontaneous emission light emitted from end faces of the quantum well active layer is polarized in a direction parallel to the substrate, and

wherein;

the substrate is a GaN substrate;

the first conductive type layer is deposited on a face tilted from a (0001) face of the GaN substrate by an angle equal to or greater than 0.05° and

smaller than 0.2°

; and

regions of high in content and regions of low in content are provided within the active layer.

11. A semiconductor light emitting element according to claim 4, wherein:

an average size of the regions in which an in content is high is from larger than 5 nm up to and including 100 nm.

14. A semiconductor light emitting element according to claim 11, wherein the semiconductor light emitting element is a semiconductor laser element.

15. A semiconductor light emitting element according to claim 14, wherein, when a half amount of threshold current is injected, a ratio of spontaneous emission light polarized in the direction parallel to the substrate and emitted from end faces of the quantum well active layer is equal to or larger than 10.