Nitride semiconductor light emitting element

• US 8,004,006 B2
• Filed: 11/07/2006
• Issued: 08/23/2011
• Est. Priority Date: 11/08/2005
• Status: Active Grant

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Yamaguchi, Atsushi, Nakahara, Ken
• Primary Examiner(s): Dickey; Thomas L
• Application Number:
  US12/084,634
• Publication Number:
  US 20090294784A1
• Time in Patent Office: 1,750 Days
• Field of Search: 257/99, 257/103
• US Class Current: 257/99
• CPC Class Codes: H01L 21/78 with subsequent division of the substrate into plural individual devices cutting to change the surface-physical characteristics or shape of semiconductor bodies H01L21/304
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating

Abstract

Provided are a nitride semiconductor light emitting element which does not suffer a damage on a light emitting region and has a high luminance without deterioration, even though the nitride semiconductor light emitting element is one in which electrodes are disposed opposite to each other and an isolation trench for chip separation and laser lift-off is formed by etching; and a manufacturing method thereof. An n-type nitride semiconductor layer 2 has a step, formed in a position beyond an active layer 3 when viewed from a p side. Up to the position of this step A, a protective insulating film 6 covers a part of the n-type nitride semiconductor layer 2, the active layer 3, a p-type nitride semiconductor layer 4, the side of a p electrode 5 and a part of the top side of the p electrode 5. The use of a structure having a chip side face covered with the protective insulating film 6 prevents the active layer or the like from being exposed to an etching gas for a long time when an isolation trench for chip separation or laser lift-off is formed by etching.

Claims

1. A nitride semiconductor light emitting element including at least an n side electrode, an n-type nitride semiconductor layer, a light emitting region, a p-type nitride semiconductor layer and a p side electrode in listed order, characterized by comprising a step provided between the light emitting element and the n side electrode, and

a first protective insulating film formed in a laminated direction from the p side electrode to the position of the step, and

a second protective insulating film formed outside the first protective insulating film and formed to the lower end of the n-type nitride semiconductor layer, the second protective insulating film having a smaller refractive index than that of the first protective insulating film,

wherein:

the n-type nitride semiconductor layer includes an upper surface, a lower surface and a side face that bridges the upper surface and the lower surface;

the n side electrode comes in contact with the lower surface of the n-type nitride semiconductor layer; and

the second protective insulating film covers the entire side face of the n-type nitride semiconductor layer.

2. The nitride semiconductor light emitting element according to claim 1, characterized in that

the first protective insulating film has a smaller refractive index than the n-type nitride semiconductor layer and the p-type nitride semiconductor layer.

3. A nitride semiconductor light emitting element including at least an n side electrode, an n-type nitride semiconductor layer, a light emitting region, a p-type nitride semiconductor layer and a p side electrode in listed order, characterized by comprising a step provided between the light emitting element and the n side electrode, and

a first protective insulating film formed in a laminated direction from the p side electrode to the position of the step, and

a second protective insulating film formed outside the first protective insulating film and formed to the lower end of the n-type nitride semiconductor layer, the second protective insulating film having a smaller refractive index than that of the first protective insulating film, wherein:

the n-type nitride semiconductor layer includes an upper surface, a lower surface and a side face that bridges the upper surface and the lower surface, the step being provided in the side face, the side face including an upper part with respect to the step and a lower part with respect to the step; and

the first protective insulating film covers only the upper part of the side face of the n-type nitride semiconductor layer, without covering the lower part of the side face of the n-type nitride semiconductor layer.

4. The nitride semiconductor light emitting element according to claim 3, characterized in that

the first protective insulating film has a smaller refractive index than the n-type nitride semiconductor layer and the p-type nitride semiconductor layer.