Semiconductor light emitting device having convex portion made with different materials

• US 9,748,453 B2
• Filed: 05/04/2016
• Issued: 08/29/2017
• Est. Priority Date: 06/22/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Jong Hak, Sakong, Tan, Sim, Eun Deok, Lee, Jeong Wook, Lim, Jin Young, Kim, Byoung Kyun
• Primary Examiner(s): HENRY, CALEB E
• Application Number:
  US15/146,372
• Publication Number:
  US 20160372643A1
• Time in Patent Office: 482 Days
• Field of Search: 257 98
• 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 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/49107 on the semiconductor or solid-state body
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/181 Encapsulation
• CPC Class Codes: H01L 2933/0083 Periodic patterns for optical field-shaping in or on the semiconductor body or semiconductor body package, e.g. photonic bandgap structures
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/58 Optical field-shaping elements

Abstract

A semiconductor light emitting device includes a substrate formed of a first material; and a convex portion protruding from the substrate and including: a first layer formed of the first material as that of the substrate; and a second layer formed of a second material different from the first material and disposed on the first layer. A second height of the second layer is greater than a first height of the first layer.

Claims

1. A semiconductor light emitting device comprising:

a substrate formed of a first material; and

a convex portion protruding from the substrate and comprising;

a first layer formed of the first material as that of the substrate; and

a second layer formed of a second material different from the first material and disposed on the first layer,

wherein a second maximum height of the second layer is greater than a first maximum height of the first layer, the first maximum height and the second maximum height being measured in a thickness direction of the semiconductor light emitting device, and

wherein the first maximum height of the first layer is measured from a surface of the substrate surrounding the convex portion.

2. The semiconductor light emitting device of claim 1, wherein a ratio of the first maximum height to a maximum height of the convex portion including the first and the second layers ranges from 0.1 to 0.4.

3. The semiconductor light emitting device of claim 1, wherein the first maximum height ranges from 240 nm to 380 nm.

4. The semiconductor light emitting device of claim 1, wherein the second material corresponds to a material having a refractive index smaller than that of the substrate.

5. The semiconductor light emitting device of claim 1, wherein the second layer comprises a plurality of materials, each of the plurality of materials having a refractive index smaller than that of the substrate.

6. The semiconductor light emitting device of claim 1, wherein a refractive index of the second layer ranges from 1 to 1.7.

7. The semiconductor light emitting device of claim 1, wherein the second layer is formed of SiO_x, SiO_xN_y, or MgF₂.

8. The semiconductor light emitting device of claim 1, wherein the second layer has a hemispherical or conic shape.

9. The semiconductor light emitting device of claim 1, wherein the convex portion comprises a plurality of protrusions, and

wherein the plurality of protrusions are arranged in a lattice form.

10. The semiconductor light emitting device of claim 1, wherein in a vertical cross-sectional view, the first layer has a side surface extending from a lower surface of the second layer, the side surface of the first layer being inclined at a first angle with respect to an upper surface of the substrate and a side surface of a lower portion of the second layer being inclined at a second angle with respect to the upper surface of a substrate, and

wherein the first angle is different from the second angle.

11. The semiconductor light emitting device of claim 1, wherein in a vertical cross-sectional view, the first layer has a side surface extending from a lower surface of the second layer, the side surface of the first layer being inclined at a first angle with respect to an upper surface of the substrate and a side surface of a lower portion of the second layer being inclined at a second angle with respect to the upper surface of a substrate, and

wherein the first angle is the same as the second angle.

12. The semiconductor light emitting device of claim 1, wherein the substrate surrounding the convex portion comprises a flat surface.

13. The semiconductor light emitting device of claim 1, wherein the substrate surrounding the convex portion comprises an uneven surface.

16. The semiconductor light emitting device of claim 1, wherein the first layer comprises:

a first surface; and

a second surface opposite to the first surface along the thickness direction of the semiconductor light emitting device, the first surface provided closer to the substrate than the second surface, and

wherein the second layer is provided on the second surface of the first layer.

18. The semiconductor light emitting device of claim 1, wherein the first surface is coplanar with the surface of the substrate surrounding the convex portion.

14. A semiconductor light emitting device comprising:

a substrate made of a first material;

a convex portion disposed on a surface of the substrate and comprising;

a first layer made of the first material; and

a second layer made of a second material different from the first material and disposed on the first layer; and

a light emitting stack comprising;

a first conductivity-type semiconductor layer;

an active layer; and

a second conductivity-type semiconductor layer, the first conductivity-type semiconductor layer, the active layer and the second conductivity-type semiconductor layer sequentially disposed on the surface of the substrate on which the convex portion is disposed,

wherein a first maximum height of the first layer ranges from 240 nm to 380 nm and a second maximum height of the second layer is 1.5 to 9 times the first maximum height of the first layer, the first maximum height and the second maximum height being measured in a thickness direction of the semiconductor light emitting device, and

wherein the first maximum height of the first layer is measured from the surface of the substrate surrounding the convex portion.

15. The semiconductor light emitting device of claim 14, wherein the substrate comprises a sapphire substrate, and

wherein the light emitting stack is formed of a Group III nitride semiconductor.

17. The semiconductor light emitting device of claim 14, wherein the first layer comprises:

a first surface; and

a second surface opposite to the first surface along the thickness direction of the semiconductor light emitting device, the first surface provided closer to the substrate than the second surface, and

wherein the second layer is provided on the second surface of the first layer.

19. The semiconductor light emitting device of claim 14, wherein the first surface is coplanar with the surface of the substrate surrounding the convex portion.