Layer-by-layer deposition using hydrogen

Patent metadata

Field	Value
Publication number	US-2018266001-A1
Application number	US-201815913542-A
Country	US
Kind code	A1
Filing date	Mar 6, 2018
Priority date	Mar 16, 2017
Publication date	Sep 20, 2018
Grant date	—

Abstract

Layer-by-layer thickness control of an electroplated film can be achieved by using a cyclic deposition process. The cyclic process involves forming a layer (or partial layer) of hydrogen on a surface of the substrate, then displacing the layer of hydrogen with a layer of metal. These steps are repeated a number of times to deposit the metal film to a desired thickness. Each step in the cycle is self-limiting, thereby enabling atomic level thickness control.

First claim

What is claimed is:

1 . A method of depositing a solid material on a substrate, the method comprising:
(a) forming a layer or a partial layer of hydrogen on a surface of the substrate; and (b) contacting the surface of the substrate with a solution comprising an ion of a material, whereby ions of the material and the hydrogen react to produce no more than about a monolayer of the material on the surface of the substrate to produce a layer or a partial layer of the material on the surface of the substrate.

2 . The method of claim 1 , further comprising repeating (a) and (b) on the surface of the substrate.

3 . The method of claim 1 , further comprising repeating (a) and (b) on the surface of the substrate at least about five times.

4 . The method of claim 1 , further comprising repeating (a) and (b) on the surface of the substrate to form a layer of the material having a thickness of between about 0.5 to 5 nanometers.

5 . The method of claim 1 , wherein the layer or partial layer of hydrogen formed in (a) has a thickness no greater than about a monolayer.

6 . The method of claim 1 , wherein forming the layer or partial layer of hydrogen comprises reducing hydrogen on the surface of the substrate.

7 . The method of claim 6 , wherein reducing hydrogen on the surface of the substrate comprises electrochemically or electrolessly reducing solvated hydrogen ions.

8 . The method of claim 6 , wherein reducing hydrogen on the surface of the substrate is performed by contacting the surface of the substrate with hydrogen species in a plasma.

9 . The method of claim 6 , wherein reducing hydrogen on the surface of the substrate is performed by contacting the surface of the substrate with hydrogen radicals.

10 . The method of claim 1 , wherein (a) and (b) are each performed in the same solution.

11 . The method of claim 10 , wherein (a) comprises applying a potential to the substrate, the potential being positive of the equilibrium electrochemical reduction potential of hydrogen gas and aqueous hydrogen ions, and wherein (b) comprises removing, reducing, or otherwise altering the potential applied to the substrate.

12 . The method of claim 1 , wherein the surface of the substrate has recessed features, at least some of which have an aspect ratio of at least about three.

13 . The method of claim 1 , wherein the surface of the substrate comprises electrically conductive regions or is entirely electrically conductive.

14 . The method of claim 1 , wherein the surface of the substrate comprises a partially fabricated semiconductor device.

15 . The method of claim 1 , wherein the material is electrically conductive.

16 . The method of claim 1 , wherein the material is a metal.

17 . The method of claim 16 , wherein the metal and its ion has an equilibrium electrochemical reduction potential that is more positive than the equilibrium electrochemical reduction potential of hydrogen gas and aqueous hydrogen ions.

18 . The method of claim 16 , wherein the metal is selected from the group consisting of gold, copper, silver, gemanium, tin, arsenic, bismuth, mercury, palladium, lead, platinum, rhenium, and molybdenum, ruthenium, and combinations thereof.

19 . The method of claim 1 , wherein the solution comprising the ion of the material is an aqueous solution.

20 . The method of claim 1 , wherein (a) and (b) are performed in different reaction vessels.

21 . The method of claim 1 , wherein (a) is performed in an apparatus comprising an anode, electrical contacts configured to apply a cathodic potential to the surface of the substrate, and a vessel configured to contain an electrolyte.

22 . The method of claim 1 , wherein (a) is performed in an apparatus comprising a chamber having a pedestal configured to support the substrate, and a remote plasma source in communication with the chamber and configured to produce hydrogen radicals.

23 . The method of claim 1 , wherein (b) is performed in an apparatus comprising electrical contacts configured to electrically couple the surface of the substrate to an external circuit, a counter electrode electrically coupled to the external circuit, and a vessel configured to contain the solution comprising the ion of the material.

24 . The method of claim 1 , wherein (a) comprises adsorbing the hydrogen on the surface of the substrate.

25 . An apparatus comprising:
(a) one or more reaction chambers configured to hold a substrate during reaction; and (b) a controller configured to cause:
(i) forming a layer or a partial layer of hydrogen on a surface of the substrate; and
(ii) contacting the surface of the substrate with a solution comprising an ion of a material, whereby ions of the material and the hydrogen react to produce no more than about a monolayer of the material on the surface of the substrate to produce a layer or a partial layer of the material on the surface of the substrate.

Assignees

• Lam Res Corp

Inventors

• Joi Aniruddha
• Dordi Yezdi

Classifications

• C25D21/12

  Process control or regulation (controlling or regulating in general G05) · CPC title

• C25D5/48

  After-treatment of electroplated surfaces · CPC title

• C23C18/1619

  Apparatus for electroless plating · CPC title

• C25D9/00

  Electrolytic coating other than with metals (C25D11/00, C25D15/00 take precedence; electrophoretic coating C25D13/00) · CPC title

• C25D5/18

  Electroplating using modulated, pulsed or reversing current · CPC title