Electrolytic copper plating bath compositions and a method for their use

Patent metadata

Field	Value
Publication number	US-10538850-B2
Application number	US-201615567637-A
Country	US
Kind code	B2
Filing date	Apr 20, 2016
Priority date	Apr 20, 2015
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

The present invention relates to aqueous acidic plating baths for copper and copper alloy deposition in the manufacture of printed circuit boards, IC substrates, semiconducting and glass devices for electronic applications. The plating bath according to the present invention comprises at least one source of copper ions, at least one acid and at least one guanidine compound. The plating bath is particularly useful for plating recessed structures with copper and build-up of copper pillar bump structures.

First claim

The invention claimed is:

1. An aqueous acidic copper plating bath for deposition of copper or copper alloys comprising at least one source of copper ions, at least one acid, and at least one guanidine compound which contains at least one unit according to formula (I)
A-D a   (I)

wherein a is an integer ranging from 1 to 40 and A represents a unit derived from a monomer according to the following formulae (A1) and/or (A2)

wherein
Y and Y′ are each individually selected from the group consisting of CH 2 , O and S;
R 1 is an organic residue selected from the group consisting of hydrogen, alkyl, aryl and alkaryl;
R 2 is an organic residue selected from the group consisting of hydrogen, alkyl, aryl and alkaryl;
R 3 , R 4 , R 5 and R 6 are each organic residues independently from each other selected from the group consisting of hydrogen, alkyl, aryl and alkaryl;
b and b′ are integers each individually and independently from each other ranging from 0 to 6;
c and c′ are integers each individually and independently from each other ranging from 1 to 6;
d and d′ are integers each individually and independently from each other ranging from 0 to 6;
e and e′ are integers each individually and independently from each other ranging from 0 to 6;
D is a divalent residue and is selected from the group consisting of
—Z 1 —[Z 2 —O] g —Z 3 —, —[Z 4 —O] h —Z 5 —, and —CH 2 —CH(OH)—Z 6 —[Z 7 —O] i —Z 8 —CH(OH)—CH 2 —;

wherein
Z 1 is an alkylene group with 1 to 6 carbon atoms;
Z 2 is selected from the group consisting of alkylene group with 1 to 6 carbon atoms, aryl-substituted alkylene groups whereby the alkylene group comprises 1 to 6 carbon atoms and mixtures of the aforementioned;
Z 3 is an alkylene group with 1 to 3 carbon atoms;
Z 4 is selected from the group consisting of alkylene group with 1 to 6 carbon atoms, aryl-substituted alkylene groups whereby the alkylene group comprises 1 to 6 carbon atoms and mixtures of the aforementioned;
Z 5 is an alkylene group with 1 to 3 carbon atoms;
Z 6 is an alkylene group with 1 to 6 carbon atoms;
Z 7 is selected from the group consisting of alkylene group with 1 to 6 carbon atoms, aryl-substituted alkylene groups whereby the alkylene group comprises 1 to 6 carbon atoms and mixtures of the aforementioned;
Z 8 is an alkylene group with 1 to 3 carbon atoms;
g is an integer ranging from 1 to 100;
h is an integer ranging from 1 to 100;
i is an integer ranging from 1 to 100; and
wherein the individual units A are selected independently from each other, and the individual units D are selected independently from each other and the guanidine compound is linear and/or cross-linked, and
wherein the bath is free of intentionally added zinc ions.

2. The aqueous acidic copper plating bath according to claim 1 characterised in that the guanidine compound comprises one or more units according to formula (I) and one or more of terminating groups P 1 and/or one or more of terminating groups P 2 whereby terminating groups P 1 are bound to a unit A derived from monomers according to formulae (A1) and/or (A2) and terminating groups P 2 are bound to divalent residues D, respectively, in the unit according to formula (I) and wherein the terminating groups P 1 are selected from the group consisting of

wherein the individual groups Z 1 to Z 8 as well as g to i are selected from above-defined groups and E is a leaving group and selected from the group consisting of triflate, nonaflate, alkylsulphonate, arylsulphonate and halogenides and wherein the terminating group P 2 is selected from the group consisting of
hydroxyl group (—OH),
a unit derived from monomers according to formulae (A1) and/or (A2),
leaving group E,

wherein the individual groups E and monomers according to formulae (A1) and/or (A2) are selected from above-defined groups.

3. The aqueous acidic copper plating bath according to claim 2 characterised in that the guanidine compound consists of a unit according to formula (I) and terminating groups P 1 and/or P 2 .

4. The aqueous acidic copper plating bath according to claim 3 characterised in that
Z 2 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned; or
Z 4 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned; or
Z 7 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned.

5. The aqueous acidic copper plating bath according to claim 4 characterised in that D is selected from —Z 1 —[Z 2 —O] g —Z 3 — and —[Z 4 —O] h —Z 5 —.

6. The aqueous acidic copper plating bath according to claim 2 characterised in that
Z 2 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned; or
Z 4 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned; or
Z 7 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned.

7. The aqueous acidic copper plating bath according to claim 1 characterised in that the guanidine compound consists of a unit according to formula (I) and terminating groups P 1 and/or P 2 .

8. The aqueous acidic copper plating bath according to claim 7 characterised in that:
Z 2 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned; or
Z 4 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned; or
Z 7 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned.

9. The aqueous acidic copper plating bath according to claim 1 characterised in that
Z 2 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned; or
Z 4 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned; or
Z 7 is selected from the group consisting of ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, butane-1,2-diyl, 1-phenylethane-1,2-diyl and mixtures of the aforementioned.

10. The aqueous acidic copper plating bath according to claim 1 characterised in that
Z 1 is an alkylene group with 2 to 3 carbon atoms;
Z 3 is an alkylene group with 2 to 3 carbon atoms;
Z 5 is an alkylene group with 2 to 3 carbon atoms;
Z 6 is an alkylene group with 2 to 3 carbon atoms;
g is an integer ranging from 1 to 20;
h is an integer ranging from 1 to 20; or
i is an integer ranging from 1 to 20.

11. The aqueous acidic copper plating bath according to

Assignees

• Atotech Deutschland Gmbh

Inventors

• Brunner Heiko
• Rohde Dirk
• Pölleth Manuel
• Rückbrod Sven
• Darwin Desthree
• Niemann Sandra
• Steinberger Gerhard

Classifications

• C25D3/38 Primary

  of copper · CPC title

• C25D21/00

  Processes for servicing or operating cells for electrolytic coating · CPC title

• C25D7/00

  Electroplating characterised by the article coated · CPC title

• C25D7/123

  Semiconductors first coated with a seed layer or a conductive layer · CPC title