LIGHT-EMITTING ELEMENT, LIGHT-EMITTING UNIT, LIGHT-EMITTING PANEL DEVICE, AND METHOD FOR DRIVING LIGHT-EMITTING PANEL DEVICE

• US 20180062047A1
• Filed: 03/24/2016
• Published: 03/01/2018
• Est. Priority Date: 03/30/2015
• Status: Active Grant

• Current Assignee: Sony Semiconductor Solutions Corporation (Sony Group Corp.)
• Original Assignee: Sony Semiconductor Solutions Corporation (Sony Group Corp.)
• Inventors: BIWA, GOSHI, OHMAE, AKIRA, KATAOKA, YUSUKE, OHASHI, TATSUO, NISHINAKA, IPPEI
• Granted Patent: US 11,158,767 B2
• Time in Patent Office: Days
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: H01L 27/153 in a repetitive configuration, e.g. LED bars
• CPC Class Codes: H01L 33/0008 having p-n or hi-lo junctions
• CPC Class Codes: H01L 33/38 with a particular shape
• CPC Class Codes: H01L 33/44 characterised by the coatings, e.g. passivation layer or anti-reflective coating
• CPC Class Codes: H01L 33/46 Reflective coating, e.g. dielectric Bragg reflector
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H05B 47/16 by timing means
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

[Object] A light-emitting element includes: a semiconductor layer; a first electrode portion; a second electrode portion; a first insulating layer; and a metal layer. The semiconductor layer includes an active layer, a first-conductivity-type layer, and a second-conductivity-type layer, and has a semiconductor-layer side surface including a side surface of the active layer, a side surface of the first-conductivity-type layer, and a side surface of the second-conductivity-type layer. The first electrode portion is connected to the first-conductivity-type layer. The second electrode portion is connected to the second-conductivity-type layer. The first insulating layer is in contact at least with a part of the semiconductor-layer side surface, the part of the semiconductor-layer side surface corresponding to a part of the side surface of the active layer. The metal layer is in contact at least with an opposed surface of the first insulating layer, the opposed surface of the first insulating layer facing the side surface of the active layer. The metal layer is conducted to the first electrode portion and insulated from the second electrode portion.

Claims

1. A light-emitting element, comprising:

a semiconductor layer including

an active layer,

a first-conductivity-type layer, and

a second-conductivity-type layer, the semiconductor layer having a semiconductor-layer side surface including

a side surface of the active layer,

a side surface of the first-conductivity-type layer, and

a side surface of the second-conductivity-type layer;

a first electrode portion connected to the first-conductivity-type layer;

a second electrode portion connected to the second-conductivity-type layer;

a first insulating layer in contact at least with a part of the semiconductor-layer side surface, the part of the semiconductor-layer side surface corresponding to a part of the side surface of the active layer; and

a metal layer in contact at least with an opposed surface of the first insulating layer, the opposed surface of the first insulating layer facing the side surface of the active layer, the metal layer being conducted to the first electrode portion and insulated from the second electrode portion.

2. The light-emitting element according to claim 1, wherein the first insulating layer and the metal layer have a laminated structure, and cover an entirety of the semiconductor-layer side surface.

3. The light-emitting element according to claim 1, wherein the second-conductivity-type layer has

a first surface which is in contact with the active layer, and

a second surface which is on an opposite side with respect to the first surface, and to which the second electrode portion is connected, the second surface serving as a light-emitting surface.

4. The light-emitting element according to claim 3, wherein

the first electrode portion includes a first connecting-conductive portion that can be connected to a substrate, the light-emitting element being mounted to the substrate, and

the metal layer is connected to the first connecting-conductive portion.

5. The light-emitting element according to claim 4, wherein

the second electrode portion includes a second connecting-conductive portion formed through the first insulating layer, and

the metal layer is connected to the second connecting-conductive portion.

6. The light-emitting element according to claim 1, wherein the first-conductivity-type layer has

a first surface which is in contact with the active layer, and

a second surface which is on an opposite side with respect to the first surface, and to which the first electrode portion is connected, the second surface serving as a light-emitting surface.

7. The light-emitting element according to claim 6, wherein the first electrode portion is connected to the metal layer across an end surface on the second surface side of the first insulating layer.

8. The light-emitting element according to claim 6, wherein

the first electrode portion includes a connecting-conductive portion formed through the first insulating layer, and

the metal layer is connected to the connecting-conductive portion.

9. The light-emitting element according to claim 1, further comprising a second insulating layer formed such that the metal layer is arranged between the first insulating layer and the second insulating layer.

10. The light-emitting element according to claim 1, wherein

the first-conductivity-type layer is a p-type semiconductor layer, and

the second-conductivity-type layer is an n-type semiconductor layer.

11. The light-emitting element according to claim 1, wherein

the first-conductivity-type layer is an n-type semiconductor layer, and

the second-conductivity-type layer is a p-type semiconductor layer.

12. The light-emitting element according to claim 6, further comprising a third electrode portion for external connection, the third electrode portion being connected to the metal layer.

13. The light-emitting element according to claim 12, further comprising a second insulating layer formed such that the metal layer is arranged between the first insulating layer and the second insulating layer, wherein

the metal layer has an opening,

the second insulating layer has

a first opening facing the opening of the metal layer, and

a second opening,

the second electrode portion is arranged on the second insulating layer so as to be in contact with the second-conductivity-type layer through the opening of the metal layer and the first opening, and

the third electrode portion is arranged on the second insulating layer so as to be in contact with the metal layer through the second opening.

14. The light-emitting element according to claim 13, wherein the second electrode portion and the third electrode portion are configured such that a part of the second electrode portion and a part of the third electrode portion are located in a common plane on the second insulating layer.

15. The light-emitting element according to claim 12, wherein the first electrode portion includes a transparent electrode.

16. The light-emitting element according to claim 12, wherein

the second insulating layer has an outer-peripheral side surface forming a side surface of the light-emitting element,

the first electrode portion has an exposed side surface, and

a contour of the exposed side surface conforms to a contour of a part of the outer-peripheral side surface of the second insulating layer.

17. The light-emitting element according to claim 12, further comprising a protective layer that covers the first-conductivity-type layer, wherein

the second insulating layer has an outer-peripheral side surface forming a side surface of the light-emitting element, and

an outer peripheral portion of the first electrode portion is arranged on an inner side with respect to the outer-peripheral side surface of the second insulating layer, and covered with the protective layer.

18. The light-emitting element according to claim 12, further comprising a protective layer including an uncovered region in which a part of the metal layer and a part of the first-conductivity-type layer are not continuously covered, the protective layer being formed on the first-conductivity-type layer,

wherein the first electrode portion is arranged in the uncovered region of the protective layer.

19. A light-emitting unit, comprising:

a substrate including a wire;

a light-emitting element; and

a joint portion that joins the light-emitting element to the wire on the substrate, the light-emitting element including

a semiconductor layer including

an active layer,

a first-conductivity-type layer, and

a second-conductivity-type layer, the semiconductor layer having a semiconductor-layer side surface including

a side surface of the active layer,

a side surface of the first-conductivity-type layer, and

a side surface of the second-conductivity-type layer,

a first electrode portion connected to the first-conductivity-type layer,

a second electrode portion connected to the second-conductivity-type layer,

a first insulating layer in contact at least with a part of the semiconductor-layer side surface, the part of the semiconductor-layer side surface corresponding to a part of the side surface of the active layer, and

a metal layer in contact with an opposed surface of the first insulating layer, the opposed surface of the first insulating layer facing the side surface of the active layer, the metal layer being conducted to the first electrode portion and insulated from the second electrode portion.

20. The light-emitting unit according to claim 19, wherein the joint portion or the wire is made of silver, copper, lead, tin, gold, nickel, palladium, or an alloy of at least two of these metals.

21. A light-emitting panel device, comprising:

a light-emitting panel including a plurality of light-emitting elements; and

a drive circuit that drives the plurality of light-emitting elements, the plurality of light-emitting elements including at least one light-emitting element including

a semiconductor layer including

an active layer,

a first-conductivity-type layer, and

a second-conductivity-type layer, the semiconductor layer having a semiconductor-layer side surface including

a side surface of the active layer,

a side surface of the first-conductivity-type layer, and

a side surface of the second-conductivity-type layer,

a first electrode portion connected to the first-conductivity-type layer,

a second electrode portion connected to the second-conductivity-type layer,

a first insulating layer in contact at least with a part of the semiconductor-layer side surface, the part of the semiconductor-layer side surface corresponding to a part of the side surface of the active layer, and

a metal layer in contact with an opposed surface of the first insulating layer, the opposed surface of the first insulating layer facing the side surface of the active layer, the metal layer being conducted to the first electrode portion and insulated from the second electrode portion.

22. The light-emitting panel device according to claim 21, further comprising a substrate, the plurality of light-emitting elements being arranged in matrix on the substrate.

23. The light-emitting panel device according to claim 21, wherein

the first-conductivity-type layer is a p-type semiconductor layer, and

the drive circuit is configured to apply a positive voltage to the first electrode portion to cause the light-emitting elements to emit light.

24. The light-emitting panel device according to claim 22, wherein

the drive circuit is configured to control timings of applying a positive voltage such that the positive voltage is applied alternately to the first electrode portion and the second electrode portion, and that a period for applying the positive voltage to the first electrode portion is longer than a period for applying the positive voltage to the second electrode portion.

25. The light-emitting panel device according to claim 24, wherein

the first-conductivity-type layer is an n-type semiconductor layer,

the second-conductivity-type layer is a p-type semiconductor layer, and

the drive circuit is configured to apply the positive voltage to a first electrode during a non-light-emission period, and to apply the positive voltage to a second electrode during a light-emission period.

26. A method for driving a light-emitting panel device, the light-emitting panel device including

a light-emitting panel including a plurality of light-emitting elements, and

a drive circuit that drives the plurality of light-emitting elements, the plurality of light-emitting elements including at least one light-emitting element including

a semiconductor layer including

an active layer,

a first-conductivity-type layer, and

a second-conductivity-type layer, the semiconductor layer having a semiconductor-layer side surface including

a side surface of the active layer,

a side surface of the first-conductivity-type layer, and

a side surface of the second-conductivity-type layer,

a first electrode portion connected to the first-conductivity-type layer,

a second electrode portion connected to the second-conductivity-type layer,

a first insulating layer in contact at least with a part of the semiconductor-layer side surface, the part of the semiconductor-layer side surface corresponding to a part of the side surface of the active layer, and

a metal layer in contact with an opposed surface of the first insulating layer, the opposed surface of the first insulating layer facing the side surface of the active layer, the metal layer being conducted to the first electrode portion and insulated from the second electrode portion, the method for driving a light-emitting panel device comprising causing the drive circuit to:

apply a positive voltage to the first electrode portion;

apply the positive voltage to the second electrode portion; and

control timings of applying the voltage such that the voltage is applied alternately to the first electrode portion and the second electrode portion, and that a period for applying the voltage to the first electrode portion is longer than a period for applying the voltage to the second electrode portion.

27. The method for driving a light-emitting panel device according to claim 26, wherein

the light-emitting panel includes a substrate, the plurality of light-emitting elements being arranged in matrix on the substrate,

the first-conductivity-type layer is an n-type semiconductor layer,

the second-conductivity-type layer is a p-type semiconductor layer, and

the method for driving a light-emitting panel device includes causing the drive circuit to apply the positive voltage to the first electrode portion during a non-light-emission period, and to apply the positive voltage to the second electrode portion during a light-emission period.