Two-step deposition with improved selectivity

Patent metadata

Field	Value
Publication number	US-2016273113-A1
Application number	US-201615165474-A
Country	US
Kind code	A1
Filing date	May 26, 2016
Priority date	Mar 25, 2014
Publication date	Sep 22, 2016
Grant date	—

Abstract

A method for providing an electroless plating over at least one copper containing layer is provided. Surfaces of the at least one copper containing layer are sealed by selectively depositing a sealing layer of catalytically active metal on the at least one copper containing layer. The sealing layer is exposed to an electroless deposition bath that is more reactive to the catalytically active metal than to the at least one copper containing layer to provide an electroless deposition on the sealing layer.

First claim

What is claimed is:

1 . A sealing bath for sealing copper layers, comprising:
a borane containing component; a metal containing reagent comprising ions of at least one of Co, Ni, or Pd; citric acid monohydrate, and boric acid.

2 . The sealing bath, as recited in claim 1 , wherein the sealing bath is oxygen free.

3 . The sealing bath, as recited in claim 2 , wherein the metal containing reagent comprises cobalt sulfate heptahydrate.

4 . The sealing bath, as recited in claim 3 , wherein the borane containing component comprises dimethylamine borane.

5 . The sealing bath, as recited in claim 4 , wherein the sealing bath has a pH of 9.

6 . The sealing bath, as recited in claim 5 , further comprising tetramethylammonium hydroxide, which is used to adjust pH.

7 . The sealing bath, as recited in claim 1 , wherein the metal containing reagent comprises cobalt sulfate heptahydrate.

8 . The sealing bath, as recited in claim 1 , wherein the borane containing component comprises dimethylamine borane.

9 . The sealing bath, as recited in claim 1 , wherein the sealing bath has a pH of 9.

10 . The sealing bath, as recited in claim 1 , further comprising tetramethylammonium hydroxide, which is used to adjust pH.

11 . The sealing bath, as recited in claim 1 , wherein the sealing bath consists essentially of 40-50 mM cobalt sulfate heptahydrate, 140-160 mM citric acid monohydrate, 75-150 mM boric acid, 25-40 mM dimethylamine borane at a pH of 9, adjusted by tetramethylammonium hydroxide.

Assignees

• Lam Res Corp

Inventors

• Kolics Artur
• Nalla Praveen
• Varadarajan Seshasayee

Classifications

• H10P14/46

  using a liquid · CPC title

• H10W20/042

  the barrier, adhesion or liner layers being seed or nucleation layers · CPC title

• H10W20/063

  by forming conductive members before forming protective insulating material · CPC title

• H10W20/057

  by selectively depositing, e.g. by using selective CVD or plating · CPC title

• H10W20/044

  for electroless plating · CPC title