Plating solution using sulfonium salt

Patent metadata

Field	Value
Publication number	US-10329680-B2
Application number	US-201615561155-A
Country	US
Kind code	B2
Filing date	Mar 24, 2016
Priority date	Mar 26, 2015
Publication date	Jun 25, 2019
Grant date	Jun 25, 2019

Abstract

A plating solution including a soluble salt containing at least a stannous salt; an acid selected from organic acid and inorganic acid or a salt thereof; and an additive containing sulfonium salt with one or more of aromatic rings is provided.

First claim

What is claimed is:

1. A plating solution for electrodeposition comprising:
(A) a soluble salt containing at least a stannous salt in an amount of 30 to 100 g/L;
(B) an acid selected from an organic acid and an inorganic acid, or a salt of the acid, in an amount of 80 to 300 g/L; and
(C) an additive, wherein
the additive comprises a sulfonium salt in an amount of 0.1 to 10 g/L, the sulfonium salt having one or more of aromatic rings represented by a general formula (1) below,

wherein, R 1 and R 2 in the formula (1) are identical or different, and are any one of a phenyl group, a hydroxyphenyl group, a tolyl group, a hydrogen atom, C n H 2n+1 , n being an integer from 1 to 5,
Ph represents a phenyl group, and
X represents a halogen.

2. The plating solution according to claim 1 , wherein
the additive further comprises a nonionic surfactant represented by a general formula (2) below,
R 3 —Y 1 —Z-Y 2 —R 4   (2)

and wherein, in the formula (2), R 3 and R 4 is represented by the formula (A) below,
—(C n H 2n —O) m —H  (A)

and wherein, Y 1 and Y 2 represent a single bond or a group selected from —O—, —COO— and —CONH—; and Z represents a benzene ring or 2,2-diphenylpropane, and
in the formula (A), n indicates 2 or 3 and m indicates an integer from 1 to 15.

3. The plating solution according to claim 2 , wherein the additive further comprises a complexing agent and an antioxidant; or one of a complexing agent and an antioxidant.

4. The plating solution according to claim 1 , wherein the additive further comprises a complexing agent and an antioxidant; or one of a complexing agent and an antioxidant.

Assignees

• Mitsubishi Materials Corp

Inventors

• Nakaya Kiyotaka
• Watanabe Mami

Classifications

• C25D3/32 Primary

  characterised by the organic bath constituents used · CPC title

• C25D3/60

  containing more than 50% by weight of tin · CPC title

• C25D7/12

  Semiconductors · CPC title

• C25D5/16

  Electroplating with layers of varying thickness · CPC title

• H05K3/188

  by direct electroplating · CPC title