# US 2014/0153203 A1 · Methods for attachment and devices produced using the methods

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

- Number: US 2014/0153203 A1
- Document ID: US20140153203A1
- Status: Published application
- Kind: A1
- Application number: 14/027,530
- Filed: 2013-09-16
- Published: 2014-06-05
- Earliest claimed: 2007-07-19
- Assignees: Alpha Metals, Inc.
- Applicants: Alpha Metals, Inc.
- Inventors: Monnir Boureghda; Nitin Desai; Anna Lifton; Oscar Khaselev; Michael T. Marczi; Bawa Singh
- Web page: https://patentgrep.com/patent/US20140153203A1

## CPC

- H10W 40/25: characterised by their materials
- H05K 13/0465: {by soldering (H05K13/0469 takes precedence)}
- B22F 1/102: Metallic powder coated with organic material
- H10W 72/01323: {in liquid form, e.g. by dispensing droplets or by screen printing}
- H10W 72/01333: {in liquid form, e.g. spin coating, spray coating or immersion coating}
- H10W 72/01338: {in gaseous form, e.g. by CVD or PVD}
- H10W 72/01351: {Changing the shapes of die-attach connectors}
- H10W 72/01353: {by etching}
- H10W 72/01365: {Thermally treating (reflowing H10W72/01357)}
- H10W 72/01971: {Cleaning, e.g. oxide removal}
- H10W 72/073: {of die-attach connectors}
- H10W 72/07311: {Treating the bonding area before connecting, e.g. by applying flux or cleaning}
- H10W 72/07331: {Connecting techniques}
- H10W 72/07332: {Compression bonding, e.g. thermocompression bonding}
- H10W 72/07334: {Using a reflow oven}
- H10W 72/07336: {Soldering or alloying}
- H10W 72/07341: {Controlling the bonding environment, e.g. atmosphere composition or temperature}
- H10W 72/07531: {Techniques}
- H10W 72/325: {Die-attach connectors having a filler embedded in a matrix}
- H10W 72/352: {comprising metals or metalloids, e.g. solders}
- H10W 72/353: {not comprising solid metals or solid metalloids, e.g. ceramics}
- H10W 72/354: {comprising polymers}
- H10W 72/552: {comprising metals or metalloids, e.g. silver}
- H10W 72/5522: {comprising gold [Au]}
- H10W 72/952: {comprising metals or metalloids, e.g. PbSn, Ag or Cu}
- H10W 90/734: {between a chip and a stacked insulating package substrate, interposer or RDL}
- H10W 90/754: {between a chip and a stacked insulating package substrate, interposer or RDL}
- Y10T 29/4913: Assembling to base an electrical component, e.g., capacitor, etc.
- Y10T 29/49133: with component orienting
- Y10T 29/49155: Manufacturing circuit on or in base
- Y10T 428/24893: including particulate material
- H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10
- H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

Methods for attachment and devices produced using such methods are disclosed. In certain examples, the method comprises disposing a capped nanomaterial on a substrate, disposing a die on the disposed capped nanomaterial, drying the disposed capped nanomaterial and the disposed die, and sintering the dried disposed die and the dried capped nanomaterial at a temperature of 300° C. or less to attach the die to the substrate. Devices produced using the methods are also described.

## Claims

### Claim 1

A method of attaching a die to a substrate, the method comprising:
disposing a capped nanomaterial on a substrate;
disposing a die on the disposed capped nanomaterial;
drying the disposed capped nanomaterial and the disposed die; and
sintering the dried disposed die and the dried capped nanomaterial at a temperature of 300° C. or less to attach the die to the substrate.

### Claim 2 (depends on 1)

The method of claim 1, in which the capped nanomaterial comprises silver particles capped with a capping agent, wherein the capping agent is present at about 10 weight percent to about 15 weight percent based on the weight of the capped silver particles.

### Claim 3 (depends on 2)

The method of claim 2, further comprising dispersing the capped silver particles in a solvent prior to disposition of the capped silver particles on the substrate.

### Claim 4 (depends on 2)

The method of claim 2, further comprising removing the capping agent from the capped silver particles during the sintering step.

### Claim 5 (depends on 1)

The method of claim 1, in which the capped nanomaterial comprises capped metal particles, wherein the metal of the capped metal particles is selected from the group consisting of gold, silver, copper, nickel, platinum, palladium, iron, and alloys thereof.

### Claim 6 (depends on 1)

The method of claim 1, in which the drying and sintering steps are performed at 300° C. or less.

### Claim 7 (depends on 1)

The method of claim 1, in which the sintering step is performed under a nitrogen atmosphere.

### Claim 8 (depends on 8)

The method of claim 8, in which the nitrogen atmosphere provides a pressure substantially equal to atmospheric pressure.

### Claim 9 (depends on 8)

The method of claim 8, in which the drying step is performed at a pressure less than atmospheric pressure.

### Claim 10

A device comprising:
a substrate;
a die disposed on the substrate; and
an electrical joint between the die and the substrate, the electrical joint comprising a nanomaterial sintered at a temperature of 300° C. or less to provide electrical coupling between the substrate and the die.

### Claim 11 (depends on 10)

The device of claim 10, in which the substrate is a printed circuit board and the nanomaterial comprises capped silver particles.

### Claim 12 (depends on 11)

The device of claim 11, in which the capped silver particles comprise about 1-3 weight percent capping agent, based on the weight of the nanomaterial, capped silver particles, prior to formation of the joint.

### Claim 13 (depends on 10)

The device of claim 10, in which the nanomaterial comprises metal particles, wherein the metal of the metal particles is selected from the group consisting of gold, silver, copper, nickel, platinum, palladium, iron, and alloys thereof.

### Claim 14 (depends on 10)

The device of claim 10, in which the electrical joint has a substantially uniform thickness between the die and the substrate.

### Claim 15 (depends on 10)

The device of claim 10, in which the electrical joint is substantially void free.

### Claim 16

A kit for producing an electrical joint, the kit comprising:
a nanomaterial comprising capped metal particles including about 10 weight percent to about 15 weight percent capping agent, based on the weight of the nanomaterial;
instructions for using the nanomaterial to provide an electrical joint between a substrate and a die disposed on the substrate.

### Claim 17 (depends on 16)

The kit of claim 16, further comprising a die for use with the nanomaterial.

### Claim 18 (depends on 17)

The kit of claim 17, further comprising a substrate for use with the die and the nanomaterial.

### Claim 19 (depends on 18)

The kit of claim 18, in which the substrate is a printed circuit board.

### Claim at position 20

20-24. (canceled)