Semiconductor light-emitting element

• US 20050035362A1
• Filed: 07/20/2004
• Published: 02/17/2005
• Est. Priority Date: 06/23/1999
• Status: Active Grant

• Current Assignee: Chisato Furukawa, Haruhiko Okazaki, Koichi Nitta, Yukio Watanabe
• Original Assignee: Chisato Furukawa, Haruhiko Okazaki, Koichi Nitta, Yukio Watanabe
• Inventors: Furukawa, Chisato, Watanabe, Yukio, Okazaki, Haruhiko, Nitta, Koichi
• Granted Patent: US 7,122,446 B2
• Time in Patent Office: Days
• US Class Current: 257/98
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 6/1225 comprising photonic band-gap structures or photonic lattices
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 33/10 with a light reflecting structure, e.g. semiconductor Bragg reflector
• CPC Class Codes: H01L 33/12 with a stress relaxation structure, e.g. buffer layer
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/405 Reflective materials

Abstract

Part of light emitted downward by an active layer is reflected by an electrode functioning as a reflective layer, and travels upward to radiate outside. Since the electrode is made of a metal, it reflects almost all light regardless of its incident angle, and light can be efficiently extracted.

Claims

1-14. -14. (Cancelled)

15. A semiconductor light-emitting element manufacturing method comprising the steps of:

forming a buffer layer on a transparent semiconductor substrate so as to be lattice-matched with the semiconductor substrate;

sequentially forming a first contact layer, a first cladding layer, a light-emitting layer, a second cladding layer, and a second contact layer on the buffer layer;

partially removing the first cladding layer, the light-emitting layer, the second cladding layer, and the second contact layer to expose a surface of the first contact layer;

forming a first electrode on the exposed surface of the first contact layer; and

forming a second light-reflecting electrode on a surface of the second contact layer.

16. A semiconductor light-emitting element manufacturing method comprising the steps of:

sequentially forming a buffer layer, a first contact layer, a first cladding layer, a light-emitting layer, a second cladding layer, and a second contact layer on a semiconductor substrate;

partially removing the first cladding layer, the light-emitting layer, the second cladding layer, and the second contact layer to expose a surface of the first contact layer;

forming a first electrode on the exposed surface of the first contact layer;

forming a second light-reflecting electrode on a surface of the second contact layer; and

forming a light extraction window at a portion of the semiconductor substrate at which the light extraction window faces the second electrode.

17. (Cancelled)

18. A semiconductor light-emitting element manufacturing method comprising the steps of:

sequentially forming a buffer layer, a first cladding layer, a light-emitting layer, a second cladding layer, and a contact layer on a transparent semiconductor substrate;

recessing a surface of the contact layer;

forming a first light-reflecting electrode on the surface of the contact layer; and

forming a second electrode on a surface of the semiconductor substrate so as to remove a portion at which the second electrode faces the first electrode.

19. A semiconductor light-emitting element manufacturing method comprising the steps of:

forming a buffer layer on a transparent semiconductor substrate so as to be lattice-matched with the semiconductor substrate;

sequentially forming a first cladding layer;

a light-emitting layer, a second cladding layer, and a contact layer on the buffer layer;

recessing a surface of the contact layer;

forming a first light-reflecting electrode on the surface of the contact layer; and

forming a second electrode on a surface of the semiconductor substrate.

20-27. -27. (Cancelled)

28. A semiconductor light-emitting element manufacturing method comprising the steps of:

sequentially forming a buffer layer, a first cladding layer, a light-emitting layer, and a second cladding layer on a first semiconductor substrate;

forming a photonics crystal layer on a second semiconductor substrate;

fusing the second cladding layer and the photonics crystal layer; and

removing the first semiconductor substrate and the buffer layer.

29. A semiconductor light-emitting element manufacturing method comprising the steps of:

sequentially forming a buffer layer, a contact layer, a first cladding layer, a light-emitting layer, and a second cladding layer on a first transparent semiconductor substrate;

forming a photonics crystal layer on a second semiconductor substrate;

fusing the first semiconductor substrate and the photonics crystal layer; and

removing the second semiconductor substrate,

when the photonics crystal layer contains a through dislocation on a light extraction surface in a substantially vertical direction to pass light emitted by the light-emitting layer.

30. A semiconductor light-emitting element manufacturing method comprising the steps of:

forming a contact layer on a semiconductor substrate;

corrugating a surface of the contact layer; and

sequentially forming a first cladding layer, a light-emitting layer, and a second cladding layer on the contact layer,

wherein a gradient index is given by the corrugated interface of the contact layer in contact with a first cladding layer, and light emitted by the light-emitting layer is reflected by the interface.

31. A semiconductor light-emitting element manufacturing method comprising the steps of:

forming at least a light-emitting layer on a semiconductor substrate; and

processing an edge of the semiconductor substrate to round the edge.

32. A semiconductor light-emitting element manufacturing method comprising the steps of:

forming a buffer layer on a first transparent semiconductor substrate;

forming a Bragg reflective layer on the buffer layer;

sequentially forming a light-emitting layer, a cladding layer, and a bonding layer on the Bragg reflective layer;

forming a photonics crystal layer on a second semiconductor substrate;

bonding the cladding layer and photonics crystal layer via the bonding layer; and

removing the second semiconductor substrate.