Sintering paste and use thereof for connecting components

Patent metadata

Field	Value
Publication number	US-12539566-B2
Application number	US-202118257037-A
Country	US
Kind code	B2
Filing date	Jul 22, 2021
Priority date	Dec 16, 2020
Publication date	Feb 3, 2026
Grant date	Feb 3, 2026

Abstract

The invention relates to a sintering paste consisting of: (A) 30 to 40 wt. % of silver flakes with an average particle size ranging from 1 to 20 μm, (B) 8 to 20 wt. % of silver particles with an average particle size ranging from 20 to 100 nm, (C) 30 to 45 wt. % of silver(I) oxide particles, (D) 12 to 20 wt. % of at least one organic solvent, (E) 0 to 1 wt. % of at least one polymer binder, and (F) 0 to 0.5 wt. % of at least one additive differing from constituents (A) to (E).

First claim

The invention claimed is:

1 . A sintering paste consisting of:
(A) 32 to 37 wt. % of silver flakes with an average particle size ranging from 1 to 20 μm; (B) 10 to 16 wt. % of silver particles with an average particle size ranging from 20 to 100 nm; (C) 32 to 40 wt. % of silver(I) oxide particles; (D) 12 to 20 wt. % of at least one organic solvent; (E) 0 to 1 wt. % of at least one polymer binder; and (F) 0 to 0.5 wt. % of at least one additive differing from constituents (A) to (E).

2 . The sintering paste according claim 1 , wherein the silver particles have an aspect ratio ranging from 1:1 to 5:1.

3 . The sintering paste according to claim 1 , wherein the silver(I) oxide particles have an average particle size ranging from 0.4 to 4 μm.

4 . The sintering paste according to claim 1 , wherein the at least one organic solvent is a combination of at least one terpineol with at least one dibasic ester.

5 . The sintering paste according to claim 1 , wherein the at least one polymer binder is selected from cellulose derivatives.

6 . The sintering paste according to claim 1 , wherein at least a portion of the silver particles is adhered to at least a portion of the silver flakes.

7 . A method for producing the sintering paste according to claim 1 , the method comprising mixing constituents (A) to (D) with one another, wherein constituents (A) and (B) are first premixed with one another.

8 . A method for connecting components, the method comprising:
(1) providing a sandwich arrangement, the sandwich arrangement comprising at least two components and a sintering paste according to claim 1 located between the components; (2) optionally drying the sintering paste; and (3) sintering the sandwich arrangement.

9 . The method according to claim 8 , wherein at least one of the at least two components consists of aluminum or an aluminum alloy.

10 . The method according to claim 8 , wherein the sintering paste is applied by means of dispensing technology.

11 . The method according to claim 8 , wherein sintering is carried out under pressure or in an unpressurized manner.

12 . The method according to claim 8 , wherein the components are component parts for electronics.

13 . A method for connecting components, the method comprising:
(1) providing a sandwich arrangement, the sandwich arrangement comprising at least two components and the sintering paste, the sintering paste produced by a method according to claim 7 and located between the components; (2) optionally drying the sintering paste; and (3) sintering the sandwich arrangement.

14 . The method of claim 13 , the method comprising drying the sintering paste.

15 . The method of claim 8 , the method comprising drying the sintering paste.

16 . The method according to claim 8 , wherein at least one of the at least two components comprises an aluminum contact surface or an aluminum-based contact surface by which the sandwich arrangement is made.

17 . The method according to claim 7 , wherein constituents (A) to (E) are mixed with one another.

18 . The method according to claim 7 , wherein constituents (A) to (F) are mixed with one another.

19 . The sintering paste of claim 1 , wherein at least one of the silver particles and the silver(I) oxide particles comprise an organic coating.

Assignees

• Heraeus Deutschland Gmbh & Co Kg

Inventors

• Chew Ly May
• Schmitt Wolfgang
• Schäfer Michael

Classifications

• B23K2103/10

  Aluminium or alloys thereof · CPC title

• B23K35/3613

  Polymers, e.g. resins · CPC title

• B23K35/3006 Primary

  Ag as the principal constituent · CPC title

• B23K35/025 Primary

  Pastes, creams or slurries · CPC title

• H10W72/07331

  Connecting techniques · CPC title