Method for no-silane electroless metal deposition using high adhesive catalyst and product therefrom

Patent metadata

Field	Value
Publication number	US-11098407-B2
Application number	US-201916565824-A
Country	US
Kind code	B2
Filing date	Sep 10, 2019
Priority date	Sep 21, 2015
Publication date	Aug 24, 2021
Grant date	Aug 24, 2021

Abstract

A method for electroless metal deposition and an electroless metal layer included substrate are provided. The method for electroless metal deposition includes steps as follows. a) cleaning a substrate, applying a hydrofluoric acid onto the substrate; and then applying a modifying agent onto the substrate to form a chemical oxide layer on the substrate; b) a catalyst layer is formed on the chemical oxide layer, wherein, the catalyst layer includes a plurality of colloidal nanoparticles, and each of the plurality of colloidal nanoparticles includes a palladium nanoparticle and a polymer which encapsulates the palladium nanoparticle, and c) depositing a metal on the catalyst layer through an electroless metal deposition to form an electroless metal layer.

First claim

What is claimed is:

1. A method for electroless metal deposition, comprising:
a) cleaning a substrate, applying a hydrofluoric acid onto the substrate, and then applying a modifying agent onto the substrate to form a chemical oxide layer on the substrate;
b) forming a catalyst layer on the chemical oxide layer, wherein the catalyst layer includes a plurality of colloidal nanoparticles, and each of the plurality of colloidal nanoparticles includes a palladium nanoparticle and a polymer which encapsulates the palladium nanoparticle, and
c) depositing a metal on the catalyst layer through an electroless metal deposition to form an electroless metal layer;
wherein, the polymer and the palladium nanoparticle have a weight ratio of 0.5:1 to 2:1.

2. The method for electroless metal deposition as claimed in claim 1 , wherein in the step a), the modifying agent is selected from the group consisting of: ozone, nitrate, hydrofluoric acid, mixture of sulfuric acid and hydrogen peroxide, and mixture of nitrate and hydrofluoric acid.

3. The method for electroless metal deposition as claimed in claim 1 , wherein the protective agent is the polymer, and the precursor is a palladium ion.

4. The method for electroless metal deposition as claimed in claim 1 , wherein each of the plurality of colloidal nanoparticles has a particle size ranging from 6 nm to 10 nm.

5. The method for electroless metal deposition as claimed in claim 1 , wherein the polymer encapsulating the palladium nanoparticle is a polyvinyl alcohol polymer, a polyvinyl alcohol acid polymer, a poly(vinyl alcohol-co-ethylene) polymer, or a poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) polymer.

6. The method for electroless metal deposition as claimed in claim 1 , wherein the polymer is a low-degree-polymerization polyvinyl alcohol polymer with a weight-average molecular weight ranging from 20000 to 30000.

7. The method for electroless metal deposition as claimed in claim 1 , wherein in the step c), the metal deposited on the catalyst layer in the electroless metal deposition is nickel or copper.

8. The method for electroless metal deposition as claimed in claim 1 , wherein the colloidal nanoparticles is formed by reacting a precursor, a protective agent, and a reducing agent in an alkaline environment.

9. The method for electroless metal deposition as claimed in claim 8 , wherein the precursor is a palladium ion, the protective agent is the polymer, and the reducing agent is a formaldehyde solution.

10. The method for electroless metal deposition as claimed in claim 8 , wherein the precursor is at least one palladium nanoparticle, the protective agent is at least one polymer, and the at least one polymer encapsulates the at least one palladium nanoparticle to form at least one colloidal nanoparticle.

11. The method for electroless metal deposition as claimed in claim 10 , wherein the at least one polymer encapsulating the at least one palladium nanoparticle is a polyvinyl alcohol polymer, a polyvinyl alcohol acid polymer, a poly(vinyl alcohol-co-ethylene) polymer, or a poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) polymer.

12. A method for metal deposition, comprising:
a) cleaning a substrate, applying a hydrofluoric acid onto the substrate, and then applying a modifying agent onto the substrate to form a chemical oxide layer on the substrate;
b) forming a catalyst layer on the chemical oxide layer, wherein the catalyst layer includes a plurality of colloidal nanoparticles, and each of the plurality of colloidal nanoparticles includes a palladium nanoparticle and a polymer which encapsulates the palladium nanoparticle, and
d) conducting an electroless metal deposition to form a metal layer on the catalyst layer;
wherein, the polymer and the palladium nanoparticle have a weight ratio of 0.5:1 to 2:1.

13. The method of claim 12 , wherein the step d) further includes conducting an electro-plating process to increase the thickness of the metal layer.

14. The method of claim 12 , wherein the step b) further includes using the polymer and a palladium ion to form the catalyst layer on the chemical oxide layer.

15. An electroless metal layer included substrate, comprising:
a chemical oxide layer formed on a surface of a substrate by cleaning the substrate, applying a hydrofluoric acid onto the substrate, and then applying a modifying agent onto the substrate;
a catalyst layer disposed on the chemical oxide layer, and the catalyst layer including a plurality of colloidal nanoparticles, and each of the plurality of colloidal nanoparticles including a palladium nanoparticle and a polymer which encapsulates the palladium nanoparticle, and
an electroless metal layer formed by conducting an electroless metal deposition to deposit a metal on the catalyst layer;
wherein, the polymer and the palladium nanoparticle have a weight ratio of 0.5:1 to 2:1.

16. The electroless metal layer included substrate as claimed in claim 15 , wherein each of the plurality of colloidal nanoparticles has a particle size ranging from 6 nm to 10 nm.

17. The electroless metal layer included substrate as claimed in claim 15 , wherein the polymer encapsulating the palladium nanoparticle includes a polyvinyl alcohol polymer, a polyvinyl alcohol acid polymer, a poly(vinyl alcohol-co-ethylene) polymer, or a poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) polymer.

18. The electroless metal layer included substrate as claimed in claim 15 , wherein the polymer is a low-degree-polymerization polyvinyl alcohol polymer with its weight-average molecular weight ranging from 20,000 to 30,000.

19. The electroless metal layer included substrate as claimed in claim 15 , wherein the metal includes nickel or copper.

Assignees

• Univ Nat Tsing Hua

Inventors

• Hsu Chin-Wei
• Wang Wei-Yen
• Wei Tzu-Chien

Classifications

• B01J35/45

  Nanoparticles · CPC title

• B01J35/23

  in a colloidal state · CPC title

• B01J37/16

  Reducing · CPC title

• C23C18/38

  Coating with copper · CPC title

• B01J33/00

  Protection of catalysts, e.g. by coating · CPC title