Solid-state element and solid-state element device

• US 20050211997A1
• Filed: 03/22/2005
• Published: 09/29/2005
• Est. Priority Date: 03/23/2004
• Status: Active Grant

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Yamaguchi, Seiji, Suehiro, Yoshinobu
• Granted Patent: US 7,429,750 B2
• Time in Patent Office: Days
• US Class Current: 257/88
• CPC Class Codes: H01L 2224/05568 the whole external layer protruding from the surface
• CPC Class Codes: H01L 2224/05573 Single external layer
• CPC Class Codes: H01L 2224/05639 Silver [Ag] as principal constituent
• CPC Class Codes: H01L 2224/05644 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/0615 Mirror array, i.e. array having only a reflection symmetry, i.e. bilateral symmetry
• CPC Class Codes: H01L 2224/14 of a plurality of bump connectors
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/17107 the bump connectors connecting two common bonding areas
• CPC Class Codes: H01L 24/05 of an individual bonding area
• CPC Class Codes: H01L 24/06 of a plurality of bonding areas
• 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 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/405 Reflective materials

Abstract

A solid-state element has: a semiconductor layer formed on a substrate, the semiconductor layer having a first layer that corresponds to an emission area of the solid-state element to and a second layer through which current is supplied to the first layer; a light discharge surface through which light emitted from the first layer is externally discharged, the light discharge surface being located on the side of the substrate; and an electrode having a plurality of regions that are of a conductive material and are in ohmic-contact with the second layer.

Claims

1. A solid-state element, comprising:

a semiconductor layer formed on a substrate, the semiconductor layer comprising a first layer that corresponds to an emission area of the solid-state element to and a second layer through which current is supplied to the first layer;

a light discharge surface through which light emitted from the first layer is externally discharged, the light discharge surface being located on the side of the substrate; and

an electrode comprising a plurality of regions that are of a conductive material and are in ohmic-contact with the second layer.

2. The solid-state element according to claim 1, wherein:

the plurality of regions are spread on the surface of the semiconductor layer, and the surface of the semiconductor layer is covered with the other conductive material with a thermal expansion coefficient that is closer to the semiconductor layer than the electrode.

3. The solid-state element according to claim 1, wherein:

the plurality of regions are connected to each other.

4. The solid-state element according to claim 1, wherein:

the conductive material does not diffuse into the semiconductor to make an intermetallic compound.

5. The solid-state element according to claim 1, wherein:

the semiconductor layer comprises a GaN based semiconductor compound.

6. The solid-state element according to claim 1, wherein:

the light discharge surface comprises an uneven surface formed by processing the substrate.

7. The solid-state element according to claim 1, wherein:

the substrate comprises a material with a refractive index substantially equal to the semiconductor layer.

8. A solid-state element, comprising:

a semiconductor layer formed on a substrate, the semiconductor layer comprising a first layer that corresponds to an emission area of the solid-state element to and a second layer through which current is supplied to the first layer;

a light discharge surface through which light emitted from the first layer is externally discharged, the light discharge surface being located on the side of the substrate;

a contact electrode layer with a thermal expansion coefficient substantially equal to the solid-state element; and

a joint portion that is formed partially on the contact electrode layer and is connected to an external wiring portion.

9. The solid-state element according to claim 8, wherein:

the joint portion comprises nickel (Ni) formed a thick film.

10. The solid-state element according to claim 8, wherein:

the semiconductor layer comprises a light-emitting layer to emit light based on current supplied thereto.

11. A solid-state element device, comprising:

a solid-state element;

a mount substrate on which the solid-state element is mounted, the mount substrate having a thermal expansion coefficient substantially equal to the solid-state element; and

an inorganic seal portion that seals the solid-state element,

wherein the solid-state element comprises a contact electrode layer with a thermal expansion coefficient substantially equal to the solid-state element, and a joint portion that is formed on the contact electrode layer and is connected to a wiring portion formed on the mount substrate.

13. The solid-state element device according to claim 11, wherein:

the joint portion is formed partially on the contact electrode layer.

15. The solid-state element device according to claim 11, wherein:

the inorganic seal portion comprises a glass material with a thermal expansion coefficient substantially equal to the substrate.

17. The solid-state element device according to claim 11, wherein:

the contact electrode layer comprises a conductive metal oxide.

20. The solid-state element device according to claim 17, wherein:

the conductive metal oxide comprises ITO.

12. A solid-state element device, comprising:

a solid-state element comprising;

a semiconductor layer formed on a substrate, the semiconductor layer comprising a first layer that corresponds to an emission area of the solid-state element to and a second layer through which current is supplied to the first layer; and

a light discharge surface through which light emitted from the first layer is externally discharged, the light discharge surface being located on the side of the substrate;

a contact electrode layer with a thermal expansion coefficient substantially equal to the solid-state element;

a joint portion that is formed on the contact electrode layer and is connected to an external wiring portion.

a mount substrate on which the solid-state element is mounted, the mount substrate having a thermal expansion coefficient substantially equal to the solid-state element; and

an inorganic seal portion that seals the solid-state element.

14. The solid-state element device according to claim 12, wherein:

the joint portion is formed partially on the contact electrode layer.

16. The solid-state element device according to claim 12, wherein:

the inorganic seal portion comprises a glass material with a thermal expansion coefficient substantially equal to the substrate.

18. The solid-state element device according to claim 12, wherein:

the contact electrode layer comprises a conductive metal oxide.

21. The solid-state element device according to claim 18, wherein:

the conductive metal oxide comprises ITO.

19. A solid-state element device, comprising:

a solid-state element;

a mount substrate on which the solid-state element is mounted, the mount substrate being of an inorganic material with a thermal expansion coefficient substantially equal to the solid-state element; and

an inorganic seal portion that seals the solid-state element,

wherein the solid-state element comprises a contact electrode layer that comprises a conductive metal oxide, and a joint portion that is formed on the contact electrode layer and is connected to a wiring portion formed on the mount substrate.

22. The solid-state element device according to claim 19, wherein:

the conductive metal oxide comprises ITO.