Method for fabricating a nitride semiconductor light-emitting device

• US 20050186694A1
• Filed: 02/17/2005
• Published: 08/25/2005
• Est. Priority Date: 02/20/2004
• Status: Active Grant

• Current Assignee: Sharp Fukuyama Laser Co., Ltd. (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Kaneko, Yoshika, Kamikawa, Takeshi, Takakura, Teruyoshi
• Granted Patent: US 7,109,049 B2
• Time in Patent Office: Days
• US Class Current: 438/28
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01L 21/02389 Nitrides
• CPC Class Codes: H01L 21/0243 Surface structure
• CPC Class Codes: H01L 21/02433 Crystal orientation
• CPC Class Codes: H01L 21/02458 Nitrides
• CPC Class Codes: H01L 21/02505 consisting of more than two layers
• CPC Class Codes: H01L 21/0254 Nitrides
• CPC Class Codes: H01L 21/30612 Etching of AIIIBV compounds
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01S 2304/04 MOCVD or MOVPE
• CPC Class Codes: H01S 5/0202 Cleaving
• CPC Class Codes: H01S 5/2004 Confining in the direction perpendicular to the layer structure
• CPC Class Codes: H01S 5/2201 in a specific crystallographic orientation
• CPC Class Codes: H01S 5/2214 based on oxides or nitrides
• CPC Class Codes: H01S 5/2231 with inner confining structure only between the active layer and the upper electrode
• CPC Class Codes: H01S 5/305 characterised by the doping materials used in the laser structure
• CPC Class Codes: H01S 5/34333 with a well layer based on Ga(In)N or Ga(In)P, e.g. blue laser

Abstract

Provided is a method for fabricating a nitride semiconductor light-emitting device including a nitride semiconductor substrate having a groove and a ridge formed on the top surface thereof so as to extend in the shape of stripes and a nitride semiconductor growth layer consisting of a plurality of nitride semiconductor layers laid on top of the nitride semiconductor substrate. The method involves a step of forming a 10 μm or more wide flat region above at least either of the groove and ridge by forming the nitride semiconductor growth layer on top of the nitride semiconductor substrate so that the height of the nitride semiconductor growth layer laid above the groove is smaller than the height of the nitride semiconductor growth layer laid above the ridge.

Claims

1. A method for fabricating a nitride semiconductor light-emitting device, the device including:

a nitride semiconductor substrate having a groove and a ridge formed on a top surface thereof so as to extend in a shape of stripes; and

a nitride semiconductor growth layer having a plurality of nitride semiconductor layers laid on top of the nitride semiconductor substrate,

the method comprising;

a first step of forming a 10 μ

m or more wide flat region above at least either of the groove and ridge by forming the nitride semiconductor growth layer on top of the nitride semiconductor substrate so that a height of the nitride semiconductor growth layer laid above the groove is smaller than a height of the nitride semiconductor growth layer laid above the ridge;

a second step of forming an elevated ridge stripe portion on the surface of the nitride semiconductor growth layer in the flat region formed in the first step; and

a third step of performing division along at least either of the groove and ridge along a division line extending in a direction parallel to the ridge stripe portion.

2. The method of claim 1,

wherein a cross-sectional shape of the groove is rectangular, or inverted-tapered so that a width of the groove at an opening thereof is smaller than a width of the groove at a floor thereof, or regular-tapered so that the width of the groove at the opening thereof is greater than the width of the groove at the floor thereof.

3. The method of claim 1,

wherein a width of the groove formed on the nitride semiconductor substrate is 50 μ

m or more but 1,200 μ

m or less.

4. The method of claim 1,

wherein a depth of the groove formed on the nitride semiconductor substrate is 3 μ

m or more but 20 μ

m or less.

5. The method of claim 1,

wherein a layer thickness of an n-type GaN layer laid on the surface of the nitride semiconductor substrate is 0.1 μ

m or more but 2 μ

m or less.

6. The method of claim 1,

wherein an off angle of the top surface of the nitride semiconductor substrate is 0.2°

or less.

7. The method of claim 1,

wherein a width of the ridge is 70 μ

m or more but 1,200 μ

m or less.

8. The method of claim 1,

wherein the ridge stripe portion is formed in the flat region, 5 μ

m or more away from an edge of the flat region.

9. The method of claim 1,

wherein, in the third step, the division line is at least 20 μ

m away from the ridge stripe portion.

10. The method of claim 1,

wherein, in the third step, the nitride semiconductor light-emitting device formed above the groove or ridge is divided along the division line so that the nitride semiconductor light-emitting device thus divided does not include a stepped portion formed between the groove and the ridge.

11. The method of claim 1,

wherein, in the third step, the nitride semiconductor light-emitting device formed above the groove or ridge is divided along the division line so that the nitride semiconductor light-emitting device thus divided includes a stepped portion formed between the groove and the ridge.

12. The method of claim 1,

wherein, when the nitride semiconductor light-emitting device is formed above both the groove and ridge, the nitride semiconductor light-emitting device formed above the groove and ridge is divided so that one of the nitride semiconductor light-emitting devices thus divided includes a stepped portion formed between the groove and the ridge.