Electroless copper plating and counteracting passivation

Patent metadata

Field	Value
Publication number	US-2021140051-A1
Application number	US-201916679386-A
Country	US
Kind code	A1
Filing date	Nov 11, 2019
Priority date	Nov 11, 2019
Publication date	May 13, 2021
Grant date	—

Abstract

Prior to electroless copper plating on substrates containing copper, an aqueous composition containing select six-membered heterocyclic nitrogen compounds is applied to the substrate. The aqueous composition containing the select six-membered heterocyclic nitrogen compounds counteract passivation of the copper on the substrate to improve the electroless copper plating process.

First claim

1 . (canceled)

2 . A method of electroless copper plating comprising:
a) providing a substrate comprising passivated copper; b) applying a catalyst to the passivated copper of the substrate; c) treating the catalyzed passivated copper of the substrate with an aqueous composition comprising a reducing agent and a six-membered heterocyclic nitrogen compound selected from the group consisting of 2-(aminomethyl)pyridine, 2-aminopyrazine, cytosine, di-(2-picolyl)amine, 4,4′-dipyridyl, 2-(hydroxymethyl)pyridine, 3-(hydroxymethyl)pyridine and mixtures thereof; d) applying an electroless copper plating bath to the treated anti-passivated copper of the substrate; and e) electroless plating copper on the treated anti-passivated copper of the substrate with the electroless copper plating bath.

3 . The method of claim 2 , further comprising applying a conditioner to the substrate comprising the passivated copper prior to applying the catalyst.

4 . The method of claim 2 , further comprising rinsing the substrate with the catalyzed anti-passivated copper after the treatment with the aqueous composition with a water rinse solution.

5 . The method of claim 4 , wherein the water rinse solution comprises a six-membered heterocyclic nitrogen compound selected from the group consisting of 2-(aminomethyl)pyridine, 2-aminopyrazine, cytosine, di-(2-picolyl)amine, 4,4′-dipyridyl, 2-(hydroxymethyl)pyridine, 3-(hydroxymethyl)pyridine, and mixtures thereof.

6 . (canceled)

7 . The method of electroless copper plating of claim 2 , wherein the aqueous composition further comprises one or more acids.

8 - 9 . (canceled)

Assignees

• Rohm & Haas Elect Mat

Inventors

• Naab Benjamin

Classifications

• C23C18/1651

  Two or more layers only obtained by electroless plating · CPC title

• C23C18/166

  with two steps starting with addition of reducing agent followed by metal deposition · CPC title

• C23C18/1633 Primary

  Process of electroless plating · CPC title

• C23C18/1637

  metallic substrate · CPC title

• C23C18/40 Primary

  using reducing agents · CPC title