# US 2018/0026157 A1 · Ultraviolet Reflective Rough Adhesive Contact

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2018/0026157 A1
- Document ID: US20180026157A1
- Status: Published application
- Kind: A1
- Application number: 15/706,990
- Filed: 2017-09-18
- Published: 2018-01-25
- Earliest claimed: 2013-01-09
- Assignees: Sensor Electronic Technology, Inc.
- Applicants: Sensor Electronic Technology, Inc.
- Inventors: Remigijus Gaska; Maxim S. Shatalov; Alexander Dobrinsky; Jinwei Yang; Michael Shur; Grigory Simin
- Web page: https://patentgrep.com/patent/US20180026157A1

## CPC

- H10H 20/82: Roughened surfaces, e.g. at the interface between epitaxial layers
- H10D 62/8161: {potential variation due to variations in composition or crystallinity, e.g. heterojunction superlattices (lateral superlattices, lateral surface superlattices H10D62/8181)}
- H10H 20/824: comprising only Group III-V materials, e.g. GaP
- H10H 20/825: containing nitrogen, e.g. GaN
- H10H 20/831: characterised by their shape
- H10P 14/3244: {Layer structure}
- H10W 72/20: Bump connectors, e.g. solder bumps or copper pillars; Dummy bumps; Thermal bumps
- H10W 72/90: Bond pads, in general
- H10H 20/032: {of electrodes}
- H10W 72/01225: {in solid form, e.g. by using a powder or by stud bumping}
- H10W 72/07252: {changes in structures or sizes}
- H10W 72/227: {Multiple bumps having different sizes}
- H10W 72/29: Bond pads specially adapted therefor
- H10W 72/944: {Dispositions of multiple bond pads}
- H10W 90/724: {between a chip and a stacked insulating package substrate, interposer or RDL}
- H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
- H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10

## 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

### Claim 1

A device comprising:
a first semiconductor layer formed of a first group III nitride material;
a contact to the first semiconductor layer;
a second semiconductor layer located between the first semiconductor layer and the contact, wherein the second semiconductor layer comprises a second group III nitride material having a gallium molar fraction greater than 0.8, and 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 between 3 and 20 nanometers and a characteristic width within a range of approximately 0.1 micron to approximately 50 microns.

### Claim 2 (depends on 1)

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 each having a closed boundary that is separate from the second semiconductor layer and the contact, wherein some of the plurality of islands have a boundary that extends into both the second semiconductor layer and the contact.

### Claim 3 (depends on 2)

The device of claim 2, wherein the plurality of islands comprise at least one of: metal, oxide, nitride, or graphene.

### Claim 4 (depends on 2)

The device of claim 2, wherein at least some of the plurality of islands are formed of an oxide.

### Claim 5 (depends on 2)

The device of claim 2, further comprising a plurality of metallic protrusions that extend from the interlayer into at least the second semiconductor layer.

### Claim 6 (depends on 1)

The device of claim 1, wherein the characteristic height is an average vertical distance between adjacent crests and valleys of the first roughness profile, and wherein the characteristic width is an average lateral distance between adjacent crests and valleys of the first roughness profile.

### Claim 7 (depends on 1)

The device of claim 1, wherein the second semiconductor layer is laterally inhomogeneous.

### Claim 8 (depends on 1)

The device of claim 1, wherein the device is configured to operate as an ultraviolet light emitting diode

### Claim 9 (depends on 1)

The device of claim 1, wherein the first roughness profile is formed from a plurality of stepped portions of the first semiconductor layer.

### Claim 10 (depends on 1)

the device of claim 1, wherein the first semiconductor layer is a p-type semiconductor layer.

### Claim 11

A device comprising:
an active region configured to sense or emit ultraviolet light;
a first semiconductor layer formed on a p-type side of the active region;
a contact to the first semiconductor layer;
a second p-type semiconductor layer located between the first semiconductor layer and the contact, 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 between 3 and 20 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.

### Claim 12 (depends on 11)

The device of claim 11, wherein a composition of the first semiconductor layer is laterally homogeneous and a composition of the second semiconductor layer is laterally inhomogeneous.

### Claim 13 (depends on 11)

The device of claim 11, wherein the second semiconductor layer comprises a second group III nitride material having a gallium molar fraction greater than 0.8.

### Claim 14 (depends on 11)

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 each having a closed boundary that is separate from the second semiconductor layer and the contact, wherein some of the plurality of islands have a boundary that extends into both the second semiconductor layer and the contact.

### Claim 15 (depends on 14)

The device of claim 14, wherein the plurality of islands comprise at least one of:
metal, oxide, nitride, or graphene.

### Claim 16

A device comprising:
a first semiconductor layer formed of a first group III nitride material;
a contact to the first semiconductor layer, wherein an interface between the first semiconductor layer and the contact includes a first roughness profile having a characteristic height between 3 and 20 nanometers and a characteristic width within a range of approximately 0.1 micron to approximately 50 microns; and
an interlayer located between the first semiconductor layer and the contact, wherein the interlayer comprises a plurality of islands each having a closed boundary that is separate from the first semiconductor layer and the contact, wherein a first portion of the plurality of islands comprise a metal-based alloy having a high adhesion to group III nitride materials and a second portion of the plurality of islands comprise a metal to provide a low specific resistance contact to group III nitride materials.

### Claim 17 (depends on 16)

The device of claim 16, further comprising a second semiconductor layer located between the first semiconductor layer and the interlayer, wherein the second semiconductor layer comprises a second group III nitride material having a gallium molar fraction greater than 0.8.

### Claim 18 (depends on 16)

The device of claim 16, wherein a third portion of the plurality of islands comprise graphene.

### Claim 19 (depends on 16)

The device of claim 16, wherein at least some of the plurality of islands are formed of an oxide.

### Claim 20 (depends on 16)

The device of claim 16, further comprising a plurality of metallic protrusions that extend from the interlayer into the first semiconductor layer.