SEMICONDUCTOR LIGHT EMITTING DEVICE AND MANUFACTURING METHOD OF THE SAME

• US 20120228581A1
• Filed: 08/23/2011
• Published: 09/13/2012
• Est. Priority Date: 03/08/2011
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: HWANG, Jongil, Hattori, Yasushi, Hashimoto, Rei, Saito, Shinji, Tohyama, Masaki, Nunoue, Shinya, Hung, Hung
• Granted Patent: US 8,729,575 B2
• Time in Patent Office: Days
• US Class Current: 257/13
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 2304/04 MOCVD or MOVPE
• CPC Class Codes: H01S 5/0202 Cleaving
• CPC Class Codes: H01S 5/22 having a ridge or stripe structure
• CPC Class Codes: H01S 5/3063 using Mg
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser

Abstract

The semiconductor light emitting device according to an embodiment includes an N-type nitride semiconductor layer, a nitride semiconductor active layer disposed on the N-type nitride semiconductor layer, and a P-type nitride semiconductor layer disposed on the active layer. The P-type nitride semiconductor layer includes an aluminum gallium nitride layer. The indium concentration in the aluminum gallium nitride layer is between 1E18 atoms/cm³ and 1E20 atoms/cm³ inclusive. The carbon concentration is equal to or less than 6E17 atoms/cm³. Where the magnesium concentration is denoted by X and the acceptor concentration is denoted by Y, Y>{(−5.35e19)²−(X−2.70e19)²}^1/2−4.63e19 holds.

Claims

1. A semiconductor light emitting device comprising:

an N-type nitride semiconductor layer;

an active layer of a nitride semiconductor disposed on the N-type nitride semiconductor layer; and

a P-type nitride semiconductor layer disposed on the active layer,

wherein the P-type nitride semiconductor layer includes an aluminum gallium nitride layer, an indium concentration in the aluminum gallium nitride layer is between 1E18 atoms/cm³ and 1E20 atoms/cm³ inclusive, a carbon concentration is equal to or less than 6E17 atoms/cm³, and

Y>

{(−

5.35e19)²−

(X−

2.70e19)²}^1/2−

4.63e19 holds,

where X and Y denote a magnesium concentration and an acceptor concentration respectively in the aluminum gallium nitride layer.

2. The device according to claim 1, wherein the indium concentration is between 3E18 atoms/cm³ and 3E19 atoms/cm³ inclusive, the carbon concentration is equal to or less than 6E17 atoms/cm³, and the magnesium concentration is between 5E18 atoms/cm³ and 5E19 atoms/cm³ inclusive.

3. The device according to claim 1, wherein the P-type nitride semiconductor layer comprises a guiding layer of P-type gallium nitride disposed on the active layer, a cladding layer disposed on the guiding layer, and a contact layer of P-type gallium nitride disposed on the cladding layer, and

the cladding layer is the aluminum gallium nitride layer.

4. The device according to claim 1, wherein the N-type nitride semiconductor layer is an N-type gallium nitride.

5. The device according to claim 1, wherein the active layer is a gallium nitride semiconductor having a multiquantum well structure.

6. The device according to claim 1, wherein a ridge stripe is provided at the P-type nitride semiconductor layer in order to form a waveguide region for laser light.

7. A method for manufacturing a semiconductor light emitting device comprising:

forming an N-type nitride semiconductor layer, an active layer of nitride semiconductor, and a P-type nitride semiconductor layer having an aluminum gallium nitride layer including magnesium successively on a substrate by Metal Organic Chemical Vapor Deposition (MOCVD),

wherein during growth of the aluminum gallium nitride layer, a magnesium raw material, an indium raw material, and a nitrogen gas serving as a carrier gas are supplied into a growth atmosphere.

8. The method according to claim 7, wherein a growth temperature of the aluminum gallium nitride layer is between 700°

C. and 1100°

C. inclusive.

9. The method according to claim 7, wherein the amount of flow of the nitrogen gas is 10% or more with respect to the total amount of flow of the carrier gas.

10. The method according to claim 7, wherein the amount of the indium raw material supplied into the growth atmosphere during the growth of the aluminum gallium nitride layer is 50% or more with respect to a summation of the amount of supply of the aluminum raw material and the amount of supply of the gallium raw material.

11. The method according to claim 7, wherein the P-type nitride semiconductor layer comprises a guiding layer of P-type gallium nitride disposed on the active layer, a cladding layer disposed on the guiding layer, and a contact layer of P-type gallium nitride disposed on the cladding layer, and

the cladding layer is the aluminum gallium nitride layer.

12. The method according to claim 7, wherein the N-type nitride semiconductor layer is an N-type gallium nitride.

13. The method according to claim 7, wherein the active layer is a gallium nitride semiconductor having a multiquantum well structure.

14. The method according to claim 7, wherein a ridge stripe is formed on the P-type nitride semiconductor layer.