Tin or tin alloy plating solution

Patent metadata

Field	Value
Publication number	US-2020378025-A1
Application number	US-201816757872-A
Country	US
Kind code	A1
Filing date	Oct 23, 2018
Priority date	Oct 24, 2017
Publication date	Dec 3, 2020
Grant date	—

Abstract

A tin or tin alloy plating solution includes: (A) a soluble salt containing at least a stannous salt; (B) an acid selected from an organic acid and an inorganic acid or a salt thereof; (C) a surfactant; and (D) a leveling agent. In addition, the surfactant contains polyoxyethylene polyoxypropylene alkylamine, an alkyl group of the polyoxyethylene polyoxypropylene alkylamine is CaH2a+1 (where a is 12 to 18). Further, in a case where a number of a functional group of polyoxypropylene of the polyoxyethylene polyoxypropylene alkylamine is set as p and a number of a functional group of polyoxyethylene of the polyoxyethylene polyoxypropylene alkylamine is set as q, the sum of p and q (p+q) is 8 to 21, and a ratio of p to q (p/q) is 0.1 to 1.6.

First claim

1 . A method of forming a tin or tin alloy deposition layer comprising the step of forming a tin or tin alloy deposition layer on a substrate with vias having multiple kinds of via diameters by using a tin or tin alloy plating solution,
wherein the tin or tin alloy plaiting solution comprises:
(A) a soluble salt containing at least a stannous salt;
(B) an acid selected from an organic acid and an inorganic acid or a salt thereof;
(C) a surfactant; and
(D) a leveling agent,
wherein the surfactant contains polyoxyethylene polyoxypropylene alkylamine, one alkyl group and two polyoxyethylene polyoxypropylene groups are bonded to an nitrogen atom in the polyoxyethylene polyoxypropylene alkylamine, an alkyl group of the polyoxyethylene polyoxypropylene alkylamine is C a H2 a+1 (where a is 12 to 18), in a case where a number of a functional group of polyoxypropylene of the polyoxyethylene polyoxypropylene alkylamine is set as p and a number of a functional group of polyoxyethylene of the polyoxyethylene polyoxypropylene alkylamine is set as q, a sum of p and q (p+q) is 8 to 21 in each of the two polyoxyethylene polyoxypropylene groups, a ratio of p to q (p/q) is 0.1 to the leveling agent is made of a first leveling agent and a second leveling agent, the first leveling agent is one or more selected from a group consisting of aliphatic aldehyde, aromatic aldehyde, aliphatic ketone and aromatic ketone, and the second leveling agent is α,β-unsaturated carboxylic acid or α,β-unsaturated carboxylic acid amide, or a salt thereof.

2 . The method of forming a tin or tin alloy plating deposition layer according to claim 1 , wherein the tin or tin alloy plating solution further comprises two or more of: a surfactant other than the surfactant; an antioxidant; and an alcohol having 1 to 3 carbon atoms.

3 . A method for forming a bump comprising the step of performing a reflow process on the tin or tin alloy plating deposition layer formed by the method of forming a tin or tin alloy deposition layer according to claim 1 .

4 . A method for producing a circuit board using the bump formed by the method according to claim 3 .

5 . A method for forming a bump performing a reflow process comprising the step of performing a reflow process on the tin or tin alloy plating deposition layer formed by the method of forming a tin or tin alloy deposition layer according to claim 2 .

6 . A method for producing a circuit board using the bump formed by the method according to claim 5 .

Assignees

• Mitsubishi Materials Corp

Inventors

• Watanabe Mami
• SUSUKI Kyoka
• Nakaya Kiyotaka

Classifications

• H10W72/227

  Multiple bumps having different sizes · CPC title

• H10W72/012

  of bump connectors, dummy bumps or thermal bumps · CPC title

• C25D7/00

  Electroplating characterised by the article coated · CPC title

• C25D3/32 Primary

  characterised by the organic bath constituents used · CPC title

• H05K3/181

  by electroless plating (adhesives therefor H05K3/387) · CPC title