Composition for tin or tin alloy electroplating comprising leveling agent

Patent metadata

Field	Value
Publication number	US-12509790-B2
Application number	US-202118256972-A
Country	US
Kind code	B2
Filing date	Dec 15, 2021
Priority date	Dec 18, 2020
Publication date	Dec 30, 2025
Grant date	Dec 30, 2025

Abstract

Disclosed herein is an aqueous composition including tin ions, optionally alloy metal ions selected from the group consisting of silver, indium, and bismuth ions and at least one additive of formula L1aor of formula L1b

First claim

The invention claimed is:

1 . An aqueous composition comprising tin ions, optionally alloy metal ions selected from the group consisting of silver, indium, and bismuth ions and at least one additive of formula L1a

or of formula L1b

wherein
R L1 is, for each group R L1 , independently, selected from the group consisting of —F and a linear or branched C 1 to C 6 alkyl that comprises one or more F substituents in C 1 or C 2 position;
R L2 is a C 1 to C 6 alkyl, C 1 to C 6 alkenyl, C 5 to C 12 aryl, C 6 to C 15 alkylaryl, C 6 to C 15 arylalkyl, all of which may be substituted by CN, OH, C 1 to C 6 alkoxy or halogen;
R L3 is selected from the group consisting of H, C 1 to C 6 alkyl, C 1 to C 6 alkenyl, C 1 to C 6 alkoxy, halogen, CN, and OH;
R L4 is, for each R L4 independently, selected from the group consisting of R L1 and R L3 ;
R L11 , R L12 , R L13 are independently selected from the group consisting of R L1 and R L3 , with the condition that at least two of R L11 , R L12 , R L13 are R L1 ; and
X L1 is
(a) a divalent group selected from the group consisting of
(i) a C 3 to C 5 alkanediyl, and
(ii) a C 3 to C 5 alkenediyl,

or
(b) forms, together with the adjacent C═C double bond, a C 5 to C 12 aromatic ring system; and

n is the number of groups R L1 selected from the group consisting of 1, 2 and 3;
wherein the at least one additive is a fluorinated leveler capable of providing a substantially planar tin or tin alloy layer and filling features on the micrometer scale without substantially forming defects.

2 . The composition according to claim 1 , wherein R L1 is selected from the group consisting of —F, —CR 13 2 F, —CR L3 F 2 , and —CF 3 , wherein R L3 is selected from the group consisting of H and C 1 to C 6 alkyl.

3 . The composition according to claim 1 , wherein R L1 is selected from the group consisting of —F, and —CF 3 .

4 . The composition according to claim 1 , wherein R L2 is selected from the group consisting of methyl, ethyl, 1-propyl, 2-propyl, tert. butyl, and benzylidene, which may be unsubstituted or substituted by F or CN.

5 . The composition according to claim 1 , wherein the at least one additive is a compound of formula L2a

or of formula L2b

wherein
R L1a selected from the group consisting of R L1 , CI, Br, and C 1 to C 6 alkyl, which alkyl may be unsubstituted or substituted by F, CN, Cl and Br, and
m is 0, 1, 2, or 3, or 4.

6 . The composition according to claim 1 , wherein the at least one additive is a compound of formula L3

7 . The composition according to claim 1 , wherein the at least one additive is a compound of formula L3a

or of formula L3b

8 . The composition according to claim 1 , wherein the alloy metal ions comprise silver ions.

9 . The composition according to claim 1 , wherein the pH of the composition is below 4.

10 . The composition according to claim 1 , further comprising a further additive selected from the group consisting of one or more surfactants and one or more grain refiners, wherein the one or more grain refiners are different from the at least one additive.

11 . A method of using the at least one additive of formula L1a or L1b of claim 1 , the method comprising adding the at least one additive of formula L1a or L1b to a bath for depositing tin or tin alloy containing layers, wherein the tin alloy containing layers comprise an alloy metal selected from the group consisting of silver, copper, indium, and bismuth in an amount of 0.01 to 10% by weight,

or of formula L1b

wherein
R L1 is, for each group R L1 n , independently, selected from the group consisting of —F and a linear or branched C 1 to C 6 alkyl that comprises one or more F substituents in C 1 or C 2 position;
R L2 is a C 1 to C 6 alkyl, C 1 to C 6 alkenyl, C 5 to C 12 aryl, C 6 to C 15 alkylaryl, C 6 to C 15 arylalkyl, all of which may be substituted by CN, OH, C 1 to C 6 alkoxy or halogen;
R L3 is selected from the group consisting of H, C 1 to C 6 alkyl, C 1 to C 6 alkenyl, C 1 to C 6 alkoxy, halogen, CN, and OH;
R L4 is, for each R L4 independently, selected from the group consisting of R L1 and R L3 ,
R L11 , R L12 , R L13 are independently selected from the group consisting of R L1 and R L3 , with the condition that at least two of R L11 , R L12 , R L13 are R L1 , and
X L1 is
(a) a divalent group selected from the group consisting of
(i) a C 3 to C 5 alkanediyl, and
(ii) a C 3 to C 5 alkenediyl,

or
(b) forms, together with the adjacent C═C double bond, a C 5 to C 12 aromatic ring system; and

n is the number of groups RLI selected from the group consisting of 1, 2 and 3;
wherein the at least one additive is a fluorinated leveler capable of providing a substantially planar tin or tin alloy layer and filling features on the micrometer scale without substantially forming defects.

12 . The method according to claim 11 , wherein the deposited tin alloy layer has an alloy metal content of 0.1 to 5% by weight.

13 . A process for depositing a tin or tin alloy layer on a substrate by
a) contacting a tin alloy electroplating bath comprising a composition according to claim 1 with the substrate, and b) applying an electrical current to the substrate for a time sufficient to deposit the tin or tin alloy layer onto the substrate.

14 . The process according to claim 13 , wherein a tin alloy is deposited and the alloy metal content of the deposited tin alloy is from 0.01 to 10% by weight.

15 . The process according to claim 13 , wherein the substrate comprises recessed features having an aperture size from 1 to 1000 micrometers, and the deposition is performed to at least partially fill the micrometer sized recessed features.

16 . The composition according to claim 1 , wherein
R L11 , R L12 , R L13 are independently selected from the group consisting of R L1 and R L3 , with the condition that all of R L11 , R L12 , RL 13 are R L1 .

17 . The composition according to claim 1 , wherein R L2 is selected from the group consisting of methyl, ethyl, ethenyl, and benzylidene, which may be unsubstituted or substituted by F or CN.

18 . The composition according to claim 1 , wherein the at least one additive is a compound of formula L2a

or of formula L2b

Assignees

• Basf Se

Inventors

• Frischhut Sabine
• Watanabe Soichi
• Fluegel Alexander
• Arnold Marco
• Gorges Jan Niclas

Classifications

• C25D3/32 Primary

  characterised by the organic bath constituents used · CPC title

• C25D7/00

  Electroplating characterised by the article coated · CPC title

• C25D3/60 Primary

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