# US 12,218,295 B2 · Micro LED display and manufacturing method therefor

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

- Number: US 12,218,295 B2
- Document ID: US12218295B2
- Status: Granted
- Kind: B2
- Application number: 17/456,838
- Filed: 2021-11-29
- Published: 2022-03-17
- Granted: 2025-02-04
- Earliest claimed: 2019-05-29
- Assignees: Samsung Electronics Co., Ltd.; Research & Business Foundation Sungkyunkwan University
- Applicants: Samsung Electronics Co., Ltd.; Research & Business Foundation Sungkyunkwan University
- Inventors: Byunghoon Lee; Taeil Kim; Jamyeong Koo; Juseung Lee
- Web page: https://patentgrep.com/patent/US12218295B2

## CPC

- H10H 20/857: Interconnections, e.g. lead-frames, bond wires or solder balls
- H10D 86/00: Integrated devices formed in or on insulating or conducting substrates, e.g. formed in silicon-on-insulator [SOI] substrates or on stainless steel or glass substrates
- H10W 90/00: Package configurations
- H10W 99/00: Subject matter not provided for in other groups of this subclass
- H10H 20/0364: {of interconnections}
- H10W 72/01212: {at a different location than on the final device, e.g. forming solder preforms}
- H10W 72/01225: {in solid form, e.g. by using a powder or by stud bumping}
- H10W 72/072: {of bump connectors}
- H10W 72/07232: {Compression bonding, e.g. thermocompression bonding}
- H10W 72/073: {of die-attach connectors}
- H10W 72/07331: {Connecting techniques}
- H10W 72/07332: {Compression bonding, e.g. thermocompression bonding}
- H10W 72/07336: {Soldering or alloying}
- H10W 72/07338: {hardening the adhesive by curing, e.g. thermosetting}
- H10W 72/07341: {Controlling the bonding environment, e.g. atmosphere composition or temperature}
- H10W 72/228: {Multiple bumps having different structures}
- H10W 72/234: {Cross-sectional shape, i.e. in side view}
- H10W 72/241: {Dispositions, e.g. layouts}
- H10W 72/261: {Functions other than electrical connecting}
- H10W 72/30: Die-attach connectors
- H10W 72/325: {Die-attach connectors having a filler embedded in a matrix}
- H10W 72/352: {comprising metals or metalloids, e.g. solders}
- H10W 72/354: {comprising polymers}
- H10W 72/59: Bond pads specially adapted therefor
- H10W 72/90: Bond pads, in general
- H10W 72/934: {Cross-sectional shape, i.e. in side view}
- H10W 72/952: {comprising metals or metalloids, e.g. PbSn, Ag or Cu}
- H10W 74/15: on active surfaces of flip-chip devices, e.g. underfills
- H10W 80/312: {characterised by the direct bonding of electrically conductive pads}
- H10W 80/314: {characterized by direct bonding of pads or other interconnections}
- H10W 90/724: {between a chip and a stacked insulating package substrate, interposer or RDL}
- H10W 90/732: {between stacked chips}
- H10W 90/734: {between a chip and a stacked insulating package substrate, interposer or RDL}
- H10W 90/792: {between multiple chips}
- H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10

## Abstract

Various embodiments of the disclosure disclose a method for manufacturing a micro Light Emitting Diode (LED) display. The disclosed manufacturing method may include coating a face of a substrate including a circuit portion with a first thickness of a polymer adhesive solution containing a plurality of metal particles, attaching an array of micro LED chips on the polymer adhesive solution, physically connecting a connection pad for each of the array of micro LED chips to the metal particles through heating and pressing the attached plurality of micro LED chips to descend through the polymer adhesive solution, and chemically bonding the metal particles to the connection pad and the circuit portion through heating and pressing so that the micro LED chips are electrically connected to the circuit portion. Various other embodiments are also possible.

## Claims

### Claim 1

A method for manufacturing a micro Light Emitting Diode (LED) display, the method comprising:
coating a face of a substrate including a circuit portion with a first thickness of a polymer adhesive solution containing a plurality of metal particles;
attaching an array of micro LED chips on the polymer adhesive solution;
forming a space between a connection pad for each of the array of micro LED chips and the plurality of metal particles through heating and pressing applied to the polymer adhesive solution;
physically connecting the connection pad for each of the array of micro LED chips to the metal particles by the heating and the pressing the attached array of micro LED chips to descend through the polymer adhesive solution; and
chemically bonding the metal particles to the connection pad and the circuit portion by the heating and the pressing so that the micro LED chips are electrically connected to the circuit portion,
wherein the chemically bonding comprises forming an alloy formed by bonding of a portion of the plurality of metal particles with the circuit portion.

### Claim 2 (depends on 1)

The method of claim 1, wherein the substrate is constructed of a glass material.

### Claim 3 (depends on 1)

The method of claim 1, wherein each of the metal particles has a size in a range of 50 nm to 500 nm.

### Claim 4 (depends on 1)

The method of claim 1, wherein metal particles of the plurality of metal particles are alloyed with a metal material of the circuit portion at a temperature in a range of 50° C. to 300° C.

### Claim 5 (depends on 1)

The method of claim 1, wherein in the physically connecting, a physical bond is formed between metal particles of the plurality of metal particles and the connection pad of the micro LED chip by performing heat treatment at a temperature less than or equal to 100° C. or by applying a pressure less than or equal to 1N/m2.

### Claim 6 (depends on 1)

The method of claim 1, wherein the circuit portion includes a TFT circuit.

### Claim 7

A micro LED display comprising:
a substrate including a circuit portion at one face;
an array of micro LED chips attached on a polymer adhesive layer;
a 3-dimensional conductive structure disposed on a one face of the circuit portion and comprising a ridge portion and a valley portion formed to be alternately; and
a polymer adhesive layer supporting the micro LED chips and disposed between the valley portion and a connection pad of the micro LED chips, and wherein the connection pad of the micro LED chips and a peak of the ridge portion are chemically bonded.

### Claim 8 (depends on 7)

The micro LED display of claim 7, wherein the substrate is constructed of a glass material.

### Claim 9 (depends on 7)

The micro LED display of claim 7, wherein each of the micro LED chips is disposed in a connection pad-down type.

### Claim 10 (depends on 1)

The method of claim 1, wherein the array of micro LED chips includes a first portion located in the polymer adhesive solution and a second portion located outside the polymer adhesive solution.

### Claim 11 (depends on 10)

The method of claim 10, wherein the first portion occupies less than or equal to 10%, and the second portion occupies greater than or equal to 90%.

### Claim 12 (depends on 10)

The method of claim 10, wherein, when the substrate is constructed of a glass material, the first portion occupies less than or equal to 50% for each respective micro LED chip, and the second portion occupies greater than or equal to 50% for each respective micro LED chip.

### Claim 13 (depends on 1)

The method of claim 1, wherein each of the micro LED chips is disposed in a connection pad-down type.

### Claim 14 (depends on 7)

The micro LED display of claim 7, wherein the circuit portion includes a TFT circuit.