LIGHT-EMITTING DIODE, METHOD FOR MAKING LIGHT-EMITTING DIODE, INTEGRATED LIGHT-EMITTING DIODE AND METHOD FOR MAKING INTEGRATED LIGHT-EMITTING DIODE, METHOD FOR GROWING A NITRIDE-BASED III-V GROUP COMPOUND SEMICONDUCTOR, LIGHT SOURCE CELL UNIT, LIGHT-EMITTING DIODE BACKLIGHT, AND LIGHT-EMITTING DIODE DISPLAY AND ELECTRONIC DEVICE

• US 20060258027A1
• Filed: 05/16/2006
• Published: 11/16/2006
• Est. Priority Date: 05/16/2005
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Ohmae, Akira, Yanashima, Katsunori, Shiomi, Michinori, Miyajima, Takao, Yasuda, Atsushi, Ami, Takaaki, Tomiya, Shigetaka, Tange, Takashi, Maeda, Yuki
• Granted Patent: US 7,754,504 B2
• Time in Patent Office: Days
• US Class Current: 438/22
• CPC Class Codes: H01L 2224/48091 Arched
• 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 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 2924/1305 Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/12 with a stress relaxation structure, e.g. buffer layer
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers

Abstract

A method for making a light-emitting diode, which including the steps of: providing a substrate having at least one recessed portion on one main surface and growing a first nitride-based III-V group compound semiconductor layer through a state of making a triangle in section having a bottom surface of the recessed portion as a base thereby burying the recessed portion; laterally growing a second nitride-based III-V group compound semiconductor layer from the first nitride-based III-V group compound semiconductor layer over the substrate; and successively growing a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type on the second nitride-based III-V group compound semiconductor layer.

Claims

1. A method for making a light-emitting diode, which comprising the steps of:

providing a substrate having at least one recessed portion on one main surface and growing a first nitride-based III-V group compound semiconductor layer through a state of making a triangle in section having a bottom surface of the recessed portion as a base thereby burying the recessed portion;

laterally growing a second nitride-based III-V group compound semiconductor layer from the first nitride-based III-V group compound semiconductor layer over the substrate; and

successively growing a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type on the second nitride-based III-V group compound semiconductor layer.

2. The method according to claim 1, wherein in the course of the growth of the first nitride-based III-V group compound semiconductor layer, a dislocation occurring from an interface with a bottom surface of the recessed portion in a direction vertical to the one main surface arrives at an inclined face or its vicinity of a triangle having the bottom surface of the recessed portion as a base, whereupon the dislocation bends in a direction parallel to the one main surface.

3. The method according to claim 1, wherein when the first nitride-based III-V group compound semiconductor layer and the second nitride-based III-V group compound semiconductor layer are, respectively, grown, a first pit having a first width is formed in the substrate at a bottom of the recessed portion and a second pit having a second width larger than the first width is formed in the substrate at opposite sides of the recessed portion.

4. The method according to claim 1, wherein the recessed portion has an inverted trapezoid in section.

5. The method according to claim 4, wherein when a depth of the recessed portion is taken as d, a width of the bottom surface of the recessed portion is taken as W_g, and an angle established between an inclined face of the first nitride-based III-V group compound semiconductor layer in a state of a triangle in section and the one main surface of the substrate is taken as α

, d, W_g and a are so determined as to establish the relation of 2d≧

W_g tan α

.

6. The method according to claim 1, wherein the main surface has the recessed portions and the protruded portions alternately arrayed.

7. The method according to claim 1, wherein the recessed portion extends in one direction.

8. The method according to claim 1, wherein the at least one recessed portion is plural in number and the plural recessed portions extend in first and two direction mutually intersecting each other.

9. The method according to claim 1, wherein the protruded portion is hexagonal in plan and a plurality of the protruded portions are two-dimensionally arranged in a honeycomb form, and the recessed portions are formed to surround each protruded portion.

10. The method according to claim 1, wherein the substrate is one in which a nitride-based III-V group compound semiconductor layer is grown on a substrate made of a material different from a nitride-based III-V group compound semiconductor, and the recessed portion is formed in the nitride-based III-V group semiconductor layer.

11. The method according to claim 1, wherein the substrate has an amorphous layer at opposite sides of the recessed portion.

12. The method according to claim 11, wherein the amorphous layer is formed by subjecting a surface layer of the substrate to ion implantation and amorphousizing the surface layer.

13. The method according to claim 11, wherein the amorphous layer is made of an insulating film formed on the substrate.

14. The method according to claim 1, wherein a first amorphous layer, a second amorphous layer and a third amorphous layer are successively formed on the substrate at opposite sides of the recessed portion, and the second amorphous layer enables the first amorphous layer and the third amorphous layer to be selectively etched.

15. The method according to claim 1, wherein after the lateral growth of the second nitride-based III-V group compound semiconductor layer, portions other than those above the recessed portion of the second nitride-based III-V group compound semiconductor layer are removed, the third nitride-based III-V group compound semiconductor layer is laterally grown on the second nitride-based III-V group compound semiconductor layer left over the recessed portions, and the active layer and the fourth nitride-based III-V group compound semiconductor layer are successively grown on the third nitride-based III-V group compound semiconductor layer.

16. The method according to claim 1, wherein after the lateral growth of the second nitride-based III-V group compound semiconductor layer, portions other than those above the recessed portion of the second nitride-based III-V group compound semiconductor layer is removed, a fifth nitride-based III-V group compound semiconductor layer is laterally grown on the second nitride-based III-V group compound semiconductor layer left over the recessed portions, and the third nitride-based III-V group compound semiconductor layer, the active layer and the fourth nitride-based III-V group compound semiconductor layer are successively grown on the fifth nitride-based III-V group compound semiconductor layer.

17. A method for making an integrated light-emitting diode, which comprising the steps of:

growing a first nitride-based III-V group compound semiconductor layer in at least one recessed portion formed at one main surface of a substrate through a state of making a triangle in section using a bottom surface of the recessed portion as a base thereby burying the recessed portion;

laterally growing a second nitride-based III-V group compound semiconductor layer from the first nitride-based III-V group compound semiconductor layer over the substrate; and

successively growing, over the second nitride-based III-V group compound semiconductor layer, a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer.

18. A light-emitting diode, which comprising:

a substrate having at least one recessed portion on one main surface;

a sixth nitride-based III-V group compound semiconductor layer grown on the substrate without forming a space in the recessed portion; and

a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type formed over the sixth nitride-based III-V group compound semiconductor layer,

wherein a dislocation occurring, in the sixth nitride-based III-V group compound semiconductor layer, from an interface with a bottom surface of the recessed portion in a direction vertical to the one main surface arrives at an inclined face or its vicinity of a triangle having the bottom surface of the recessed portion as a base and bends in a direction parallel to the one main surface.

19. A light-emitting diode, which comprising:

a substrate having at least one recessed portion on one main surface;

a sixth nitride-based III-V group compound semiconductor layer grown on the substrate without forming a space in the recessed portion; and

a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type formed over the sixth nitride-based III-V group compound semiconductor layer,

wherein a first pit having a first width is formed in the substrate at a bottom of the recessed portion and a second pit having a second width larger than the first width is formed in the substrate at a bottom of the recessed portion.

20. An integrated light-emitting diode having a plurality of light-emitting diodes integrated, at least one light-emitting diode comprising:

a substrate having at least one recessed portion on one main surface;

a sixth nitride-based III-V group compound semiconductor layer grown on the substrate without forming a space in the recessed portion; and

a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type formed over the sixth nitride-based III-V group compound semiconductor layer,

wherein a dislocation occurring, in the sixth nitride-based III-V group compound semiconductor layer, from an interface with a bottom surface of the recessed portion in a direction vertical to the one main surface arrives at an inclined face or its vicinity of a triangle having the bottom surface of the recessed portion as a base and bends in a direction parallel to the one main surface.

21. A method for growing a nitride-based III-V group compound semiconductor layer, which comprising the steps of:

providing a substrate having at least one recessed portion on one main surface and growing a first nitride-based III-V group compound semiconductor layer through a state of making a triangle in section having a bottom surface of the recessed portion as a base and burying the recessed portion; and

laterally growing a second nitride-based III-V group compound semiconductor layer from the first nitride-based compound semiconductor layer over the substrate.

22. A light source cell unit which comprises a printed circuit board and a plurality of cells formed on the printed circuit board, each cell containing at least one red light-emitting diode, at least one green light-emitting diode and at least one blue light-emitting diode, wherein at least one of the red light-emitting diode, the green light-emitting diode and the blue light-emitting diode includes:

a substrate having at least one recessed portion on one main surface;

a sixth nitride-based III-V group compound semiconductor layer grown on the substrate without forming a space in the recessed portion; and

a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type formed over the sixth nitride-based III-V group compound semiconductor layer,

wherein a dislocation occurring from an interface with a bottom surface of the recessed portion in a direction vertical to the one main surface in the sixth nitride-based III-V group compound semiconductor layer arrives at an inclined face or its vicinity of a triangle having the bottom surface of the recessed portion as a base and bends in a direction parallel to the one main surface.

23. A light-emitting diode backlight which comprises plural red light-emitting diode, plural green light-emitting diode and plural blue light-emitting diode arranged in pattern, wherein at least one of the red light-emitting diode, the green light-emitting diode and the blue light-emitting diode includes:

a substrate having at least one recessed portion on one main surface;

a sixth nitride-based III-V group compound semiconductor layer grown on the substrate without forming a space in the recessed portion; and

a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type formed over the sixth nitride-based III-V group compound semiconductor layer,

wherein a dislocation occurring, in the sixth nitride-based III-V group compound semiconductor layer, from an interface with a bottom surface of the recessed portion in a direction vertical to the one main surface arrives at an inclined face or its vicinity of a triangle having the bottom surface of the recessed portion as a base and bends in a direction parallel to the one main surface.

24. A light-emitting diode display which comprises plural red light-emitting diodes, plural green light-emitting diodes and plural blue light-emitting diodes arranged in pattern, wherein at least one of the red light-emitting diode, the green light-emitting diode and the blue light-emitting diode includes:

a substrate having at least one recessed portion on one main surface;

a sixth nitride-based III-V group compound semiconductor layer grown on the substrate without forming a space in the recessed portion; and

a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type formed over the sixth nitride-based III-V group compound semiconductor layer,

wherein a dislocation occurring, in the sixth nitride-based III-V group compound semiconductor layer, from an interface with a bottom surface of the recessed portion in a direction vertical to the one main surface arrives at an inclined face or its vicinity of a triangle having the bottom surface of the recessed portion as a base and bends in a direction parallel to the one main surface.

25. An electronic device having at least one light-emitting diode, at least the one light-emitting diode comprising:

a substrate having at least one recessed portion on one main surface;

a sixth nitride-based III-V group compound semiconductor layer grown on the substrate without forming a space in the recessed portion; and

a third nitride-based III-V group compound semiconductor layer of a first conduction type, an active layer and a fourth nitride-based III-V group compound semiconductor layer of a second conduction type formed over the sixth nitride-based III-V group compound semiconductor layer,

wherein a dislocation occurring, in the sixth nitride-based III-V group compound semiconductor layer, from an interface with a bottom surface of the recessed portion in a direction vertical to the one main surface arrives at an inclined face or its vicinity of a triangle having the bottom surface of the recessed portion as a base and bends in a direction parallel to the one main surface.