Ultraviolet reflective rough adhesive contact

• US 9,768,357 B2
• Filed: 02/12/2016
• Issued: 09/19/2017
• Est. Priority Date: 01/09/2013
• Status: Active Grant

• Current Assignee: Sensor Electronic Technology Incorporated (Seoul Semiconductor Co., Ltd.)
• Original Assignee: Sensor Electronic Technology Incorporated (Seoul Semiconductor Co., Ltd.)
• Inventors: Gaska, Remigijus, Shatalov, Maxim S., Dobrinsky, Alexander, Yang, Jinwei, Shur, Michael, Simin, Grigory
• Primary Examiner(s): Stark, Jarrett
• Assistant Examiner(s): Ahmed, Shahed
• Application Number:
  US15/042,433
• Publication Number:
  US 20160172544A1
• Time in Patent Office: 585 Days
• Field of Search: 257 13, 257739, 257103, 257 98, 257309, 438 29, 438 69, 438669, 438478, 438 47, 438 71
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/06102 the bonding areas being at different heights
• CPC Class Codes: H01L 2224/1134 Stud bumping, i.e. using a wire-bonding apparatus
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 24/00 Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
• CPC Class Codes: H01L 24/05 of an individual bonding area
• CPC Class Codes: H01L 24/16 of an individual bump connector
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/12041 LED
• CPC Class Codes: H01L 2924/12042 LASER
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 33/007 comprising nitride compounds
• CPC Class Codes: H01L 33/0095 Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• 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 33/38 with a particular shape
• CPC Class Codes: H01L 33/405 Reflective materials

Abstract

A device including a first semiconductor layer and a contact to the first semiconductor layer is disclosed. An interface between the first semiconductor layer and the contact includes a first roughness profile having a characteristic height and a characteristic width. The characteristic height can correspond to an average vertical distance between crests and adjacent valleys in the first roughness profile. The characteristic width can correspond to an average lateral distance between the crests and adjacent valleys in the first roughness profile.

Claims

1. A device comprising:

a first semiconductor layer;

a contact to the first semiconductor layer;

a second semiconductor layer located between the first semiconductor layer and the contact, wherein a composition of the first semiconductor layer is laterally homogeneous and a composition of the second semiconductor layer is laterally inhomogeneous, and wherein an interface between the second semiconductor layer and the contact includes a first roughness profile having a characteristic height of at least three nanometers and a characteristic width of at least 0.1 micron.

2. The device of claim 1, further comprising a 2D gas at an interface between the first semiconductor layer and the second semiconductor layer.

3. The device of claim 1, further comprising a second roughness profile at an interface between the first semiconductor layer and the second semiconductor layer.

4. The device of claim 3, wherein the first and second roughness profiles are periodic.

5. The device of claim 4, wherein the first and second roughness profiles form a photonic crystal.

6. The device of claim 1, further comprising an interlayer located between the second semiconductor layer and the contact, wherein the interlayer comprises a plurality of islands.

7. The device of claim 6, further comprising a plurality of protrusions that extend from the interlayer into at least the second semiconductor layer.

8. The device of claim 6, wherein the plurality of islands includes islands formed of at least one of:

a metal, an oxide, a nitride, or graphene.

9. The device of claim 6, wherein at least one of the plurality of protrusions includes a set of sharp edges.

10. The device of claim 1, wherein the first roughness profile is at least 10% different at a center location of the device than at an edge location of the device.

11. A device comprising:

a first semiconductor layer;

a contact to the first semiconductor layer;

a second semiconductor layer located between the first semiconductor layer and the contact, wherein a composition of the first semiconductor layer is laterally homogeneous and a composition of the second semiconductor layer is laterally inhomogeneous, wherein an interface between the second semiconductor layer and the contact includes a first roughness profile with a characteristic height and a characteristic width, wherein the characteristic height is an average vertical distance between adjacent crests and valleys of the first roughness profile, and is at least approximately three nanometers, and wherein the characteristic width is an average lateral distance between adjacent crests and valleys of the first roughness profile, and is within a range of approximately 0.1 micron to approximately fifty microns.

12. The device of claim 11, further comprising a 2D gas at an interface between the first semiconductor layer and the second semiconductor layer.

13. The device of claim 11, further comprising a second roughness profile at an interface between the first semiconductor layer and the second semiconductor layer.

14. The device of claim 11, further comprising an interlayer located between the second semiconductor layer and the contact, wherein the interlayer comprises a plurality of islands.

15. The device of claim 14, wherein the plurality of islands includes islands formed of at least one of:

a metal, an oxide, a nitride, or graphene.

16. The device of claim 14, further comprising a plurality of protrusions that extend from the interlayer into at least the second semiconductor layer.

17. The device of claim 16, wherein at least one of the plurality of protrusions includes a set of sharp edges.

18. The device of claim 11, wherein the first roughness profile is at least 10% different at a center location of the device than at an edge location of the device.

19. A method comprising:

fabricating a device, the device comprising;

a first semiconductor layer;

a contact to the first semiconductor layer;

a second semiconductor layer located between the first semiconductor layer and the contact, wherein a composition of the first semiconductor layer is laterally homogeneous and a composition of the second semiconductor layer is laterally inhomogeneous, wherein an interface between the second semiconductor layer and the contact includes a first roughness profile having a characteristic height of at least three nanometers and a characteristic width of at least 0.1 micron.

20. The method of claim 19, wherein the fabricating includes:

depositing an interlayer over the first and second semiconductor layers;

patterning and annealing the interlayer, such that a plurality of protrusions extend from the interlayer into at least the second semiconductor layer;

depositing a metallic layer over the interlayer;

etching at least one of;

the interlayer or the second semiconductor layer using the metallic layer as a mask; and

depositing a reflective material into the etched regions.