Electroless plating method and ceramic substrate

Patent metadata

Field	Value
Publication number	US-2016007476-A1
Application number	US-201414760758-A
Country	US
Kind code	A1
Filing date	Feb 4, 2014
Priority date	Feb 8, 2013
Publication date	Jan 7, 2016
Grant date	—

Abstract

Provided is an electroless plating method for a low temperature co-fired glass ceramic substrate, the method including: a degreasing and activation treatment step of degreasing and activating a surface of a wiring pattern formed of a silver sintered body; a catalyzing step of providing a catalyst onto the surface of the wiring pattern formed of a silver sintered body; and an electroless multi-layered coating plating treatment step. The electroless plating method further includes, between the degreasing and activation treatment step and the catalyzing step, a silver precipitation treatment step of precipitating silver on a glass component present on the surface of the wiring pattern formed of a silver sintered body after the degreasing and activation treatment step, and the catalyzing step includes providing the catalyst also to the silver precipitated in the silver precipitation treatment step.

First claim

1 . An electroless plating method for a glass ceramic substrate comprising an insulating base material formed of glass ceramic, and a wiring pattern formed of a silver sintered body, the electroless plating method comprising:
a degreasing and activation treatment step of degreasing and activating a surface of the wiring pattern formed of a silver sintered body; a catalyzing step of providing a catalyst onto the surface of the wiring pattern formed of a silver sintered body after the degreasing and activation treatment step; and an electroless multi-layered coating plating treatment step of forming a multi-layered electroless plating coating on the surface of the wiring pattern formed of a silver sintered body on which the catalyst is provided, the electroless plating method further comprising, between the degreasing and activation treatment step and the catalyzing step, a silver precipitation treatment step of precipitating silver on a glass component present on the surface of the wiring pattern formed of a silver sintered body after the degreasing and activation treatment step, the catalyzing step comprising providing the catalyst also to the silver precipitated in the silver precipitation treatment step.

2 . An electroless plating method according to claim 1 , wherein the electroless multi-layered coating plating treatment step comprises:
an electroless nickel plating step of forming an electroless nickel plating coating on the surface of the wiring pattern formed of a silver sintered body on which the catalyst is provided; an electroless palladium plating step of forming an electroless palladium plating coating on the electroless nickel plating coating; and a substitution-type electroless gold plating step of forming a substitution-type electroless gold plating coating on the electroless palladium plating coating.

3 . An electroless plating method according to claim 2 , further comprising, between the electroless nickel plating step and the electroless palladium plating step, a glass etching treatment step of dissolving fine particles formed on glass ceramic with a glass etching liquid to remove the fine particles.

4 . An electroless plating method according to claim 1 , wherein the electroless multi-layered coating plating treatment step comprises:
an electroless nickel plating step of forming an electroless nickel plating coating on the surface of the wiring pattern formed of a silver sintered body on which the catalyst is provided; a substitution-type electroless gold plating step of forming a substitution-type electroless gold plating coating on the electroless nickel plating coating; and a reduction-type electroless gold plating step of forming a reduction-type electroless gold plating coating on the substitution-type electroless gold plating coating.

5 . An electroless plating method according to claim 4 , further comprising, between the electroless nickel plating step and the substitution-type electroless gold plating step, a glass etching treatment step of dissolving fine particles formed on glass ceramic with a glass etching liquid to remove the fine particles.

6 . An electroless plating method according to claim 1 , wherein the silver precipitation treatment step comprises:
using, as reducing agents, a phosphoric acid compound and an organic acid as first reducing agents, and an inorganic compound as a second reducing agent; and using a silver precipitation treatment liquid containing any one of the first reducing agents or a combination of any one of the first reducing agents and the second reducing agent.

7 . An electroless plating method according to claim 6 , wherein the phosphoric acid compound comprises hypophosphorous acid, sodium hypophosphite, or potassium hypophosphite.

8 . An electroless plating method according to claim 6 , wherein the organic acid comprises formic acid or citric acid.

9 . An electroless plating method according to claim 6 , wherein the inorganic compound comprises iron(II) chloride, iron(II) sulfate, or sodium thiosulfate.

10 . A glass ceramic substrate, comprising an insulating base material formed of glass ceramic, and a wiring pattern formed of a silver sintered body,
precipitated silver being scattered in a particulate form on a glass component present on a surface of the wiring pattern formed of a silver sintered body, a nickel plating coating being formed on the wiring pattern formed of a silver sintered body including the glass component and the silver scattered on the glass component, a palladium plating coating being formed on the nickel plating coating, a gold plating coating being formed on the palladium plating coating.

11 . A glass ceramic substrate, comprising an insulating base material formed of glass ceramic, and a wiring pattern formed of a silver sintered body,
precipitated silver being scattered in a particulate form on a glass component present on a surface of the wiring pattern formed of a silver sintered body, a nickel plating coating being formed on the wiring pattern formed of a silver sintered body including the glass component and the silver scattered on the glass component, a gold plating coating being formed on the nickel plating coating.

12 . A glass ceramic substrate according to claim 10 or 11 , wherein the silver scattered in a particulate form on the glass component present on the surface of the wiring pattern formed of a silver sintered body has a particle size of from 10 to 100 nm.

13 . A glass ceramic substrate according to claim 11 , wherein the silver scattered in a particulate form on the glass component present on the surface of the wiring pattern formed of a silver sintered body has a particle size of from 10 to 100 nm.

Assignees

• Mitsubishi Electric Corp

Inventors

• Takemoto Yohei
• Sekino Shiro
• Kaihatsu Yuta
• Yamanaka Hiromi

Classifications

• H05K1/092

  Dispersed materials, e.g. conductive pastes or inks · CPC title

• Y10T428/24917

  including metal layer · CPC title

• C23C18/44

  using reducing agents · CPC title

• H05K3/185 Primary

  by making a catalytic pattern by photo-imaging · CPC title

• C23C18/1639

  Substrates other than metallic, e.g. inorganic or organic or non-conductive · CPC title