# US 2021/0240080 A1 · Silicon-based nanowire, preparation method thereof, and thin film transistor

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

- Number: US 2021/0240080 A1
- Document ID: US20210240080A1
- Status: Published application
- Kind: A1
- Application number: 17/048,301
- Filed: 2020-03-25
- Published: 2021-08-05
- Earliest claimed: 2019-05-08
- Assignees: Boe Technology Group Co., Ltd.
- Applicants: Boe Technology Group Co., Ltd.
- Inventors: Xue DONG; Guangcai YUAN; Feng GUAN
- Web page: https://patentgrep.com/patent/US20210240080A1

## CPC

- G03F 7/075: Silicon-containing compounds
- G03F 7/0002: {Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping}
- G03F 7/0047: {characterised by additives for obtaining a metallic or ceramic pattern, e.g. by firing}
- G03F 7/11: having cover layers or intermediate layers, e.g. subbing layers {(G03F7/091 - G03F7/093, B41N3/03 take precedence)}
- H10D 30/674: {characterised by the active materials}
- H10D 30/6743: {Silicon}
- H10D 30/6757: {characterised by the structure of the channel, e.g. transverse or longitudinal shape or doping profile (TFTs having channel structures for preventing kink or snapback effects H10D30/6708; TFTs having lightly-doped source or drain extensions H10D30/6715)}
- H10D 62/119: {Nanowire, nanosheet or nanotube semiconductor bodies}
- H10P 95/00: Generic processes or apparatus for manufacture or treatments not covered by the other groups of this subclass
- B82Y 30/00: Nanotechnology for materials or surface science, e.g. nanocomposites
- B82Y 40/00: Manufacture or treatment of nanostructures
- C01B 33/021: Preparation (chemical coating from the vapour phase C23C16/00)
- C01P 2004/16: Nanowires or nanorods, i.e. solid nanofibres with two nearly equal dimensions between 1-100 nanometer
- G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G)
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
- B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C}
- C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS

## Abstract

The present disclosure discloses a silicon-based nanowire, a preparation method thereof, and a thin film transistor. By using a eutectic point of catalyst particles and silicon, and a driving factor that the Gibbs free energy of amorphous silicon is greater than that of crystalline silicon, and due to absorption of the amorphous silicon by the molten catalyst particles to form a supersaturated silicon eutectoid, the silicon nucleates and grows into silicon-based nanowires. Moreover, during the growth of the silicon-based nanowire, the amorphous silicon film grows linearly along guide slots under the action of the catalyst particles, and reverse growth of the silicon-based nanowire is restricted by the retaining walls, thus obtaining silicon-based nanowires with a high density and high uniformity. Furthermore, by controlling the size of the catalyst particles and the thickness of the amorphous silicon film, the width of the silicon-based nanowire may also be controlled.

## Claims

### Claim 1

A method for preparing a silicon-based nanowire, comprising:
forming catalyst particles, guide walls and retaining walls on a base substrate, wherein:
the guide walls extend in a first direction;
the retaining walls and the guide walls intersect and are located in a same layer; and
the catalyst particles are located in areas defined by the retaining walls and the guide walls, and have a eutectic point with silicon;
forming an amorphous silicon film covering the catalyst particles, the guide walls and the retaining walls; and
forming silicon-based nanowires by annealing the amorphous silicon film to a growth of amorphous silicon from the catalyst particles and along the first direction.

### Claim 2 (depends on 1)

The method of claim 1, wherein the forming the catalyst particles, the guide walls and the retaining walls on the base substrate comprises:
forming a dielectric layer on the base substrate;
forming a pattern of the guide walls and a pattern of the retaining walls by patterning the dielectric layer;
forming a catalyst film layer on the base substrate formed with the pattern of the guide walls and the pattern of the retaining walls; and
forming a pattern of the catalyst particles in the catalyst film layer.

### Claim 3 (depends on 1)

The method of claim 1, wherein the forming the catalyst particles, the guide walls and the retaining walls on the base substrate, comprises:
forming a catalyst film layer on the base substrate;
forming a pattern of the catalyst particles in the catalyst film layer;
forming a dielectric layer on the base substrate formed with the pattern of the catalyst particles; and
forming a pattern of the guide walls and a pattern of the retaining walls by patterning the dielectric layer.

### Claim 4 (depends on 2)

The method of claim 2, wherein the forming the pattern of the catalyst particles in the catalyst film layer, comprises:
forming an imprint resist on the catalyst film layer;
forming a pattern of imprint resist particles by a nanoimprint process on the imprint resist; and
forming the pattern of the catalyst particles by etching the catalyst film layer with the pattern of the imprint resist particles as a mask pattern.

### Claim 5 (depends on 2)

The method of claim 2, wherein the forming the pattern of the catalyst particles in the catalyst film layer, comprises:
forming an imprint resist on the catalyst film layer;
forming a pattern of imprint resist lines by a nanoimprint process on the imprint resist, wherein an extending direction of the imprint resist lines equals to an extending direction of the retaining walls;
form a pattern of catalyst lines by etching the catalyst film layer with the pattern of the imprint resist lines as a mask pattern; and
forming the pattern of the catalyst particles by plasma bombardment on the catalyst lines.

### Claim 6 (depends on 5)

The method of claim 5, wherein a width of a catalyst line is in a range from 50 nm to 1000 nm.

### Claim 7 (depends on 2)

The method of claim 2, wherein the forming the pattern of the catalyst particles in the catalyst film layer, comprises:
forming a photoresist on the catalyst film layer;
forming a pattern of photoresist particles by an exposure and developing process of the photoresist; and
forming the pattern of the catalyst particles by etching the catalyst film layer with the pattern of the photoresist particles as a mask pattern.

### Claim 8 (depends on 1)

The method of claim 1, wherein a material of the catalyst particles is indium, tin, nickel, or indium oxide.

### Claim 9 (depends on 1)

The method of claim 1, wherein heights of the guide walls and heights of the retaining walls are greater than or equal to particle diameters of the catalyst particles.

### Claim 10 (depends on 1)

The method of claim 1, wherein particle diameters of the catalyst particles are in a range from 1 nm to 5000 nm.

### Claim 11 (depends on 1)

The method of claim 1, wherein heights of the guide walls are in a range from 5 nm to 5000 nm, and heights of the retaining walls are in a range from 5 nm to 5000 nm.

### Claim 12 (depends on 1)

The method of claim 1, wherein the eutectic point of the catalyst particles and silicon is within a temperature range from 200° C. to 1000° C.; and
an annealing temperature is in a range from 200° C. to 600° C. in the annealing of the amorphous silicon film.

### Claim 13 (depends on 1)

The method of claim 1, comprising:
forming the catalyst particles close to the retaining walls.

### Claim 14 (depends on 13)

The method of claim 13, wherein within an area defined by the retaining walls and the guide walls, the catalyst particles are in contact with a same retaining wall, and at least part of the catalyst particles is in contact with at least one guide wall.

### Claim 15 (depends on 1)

The method of claim 1, wherein within each area defined by the retaining walls and the guide walls, one or more of the catalyst particles are formed.

### Claim 16

A silicon-based nanowire, wherein the silicon-based nanowire is prepared by:
forming catalyst particles, guide walls and retaining walls on a base substrate, wherein:
the guide walls extend in a first direction;
the retaining walls and the guide walls intersect and are located in a same layer; and
the catalyst particles are located in areas defined by the retaining walls and the guide walls, and have a eutectic point with silicon;
forming an amorphous silicon film covering the catalyst particles, the guide walls and the retaining walls; and
forming silicon-based nanowires by annealing the amorphous silicon film to a growth of amorphous silicon from the catalyst particles and along the first direction.

### Claim 17 (depends on 16)

A thin film transistor, comprising a source, a drain, a gate and an active layer, wherein a material of the active layer comprises the silicon-based nanowire of claim 16.

### Claim 18 (depends on 2)

The method of claim 2, wherein the forming the pattern of the catalyst particles in the catalyst film layer, comprises:
forming an imprint resist on the catalyst film layer;
forming a pattern of imprint resist particles by a nanoimprint process on the imprint resist; and
forming the pattern of the catalyst particles by etching the catalyst film layer with the pattern of the imprint resist particles as a mask pattern.

### Claim 19 (depends on 2)

The method of claim 2, wherein the forming the pattern of the catalyst particles in the catalyst film layer, comprises:
forming an imprint resist on the catalyst film layer;
forming a pattern of imprint resist lines by a nanoimprint process on the imprint resist, wherein an extending direction of the imprint resist lines equals to an extending direction of the retaining walls;
form a pattern of catalyst lines by etching the catalyst film layer with the pattern of the imprint resist lines as a mask pattern; and
forming the pattern of the catalyst particles by plasma bombardment on the catalyst lines;
wherein a width of a catalyst line is in a range from 50 nm to 1000 nm.

### Claim 20 (depends on 2)

The method of claim 2, wherein the forming the pattern of the catalyst particles in the catalyst film layer, comprises:
forming a photoresist on the catalyst film layer;
forming a pattern of photoresist particles by an exposure and developing process of the photoresist; and
forming the pattern of the catalyst particles by etching the catalyst film layer with the pattern of the photoresist particles as a mask pattern.