Method for copper plating through silicon vias using wet wafer back contact

Patent metadata

Field	Value
Publication number	US-10879116-B2
Application number	US-201414896854-A
Country	US
Kind code	B2
Filing date	May 27, 2014
Priority date	Jun 17, 2013
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

A method and apparatus for processing a substrate are provided. In some implementations, the method comprises providing a silicon substrate having an aperture containing an exposed silicon contact surface at a bottom of the aperture, depositing a metal seed layer on the exposed silicon contact surface and exposing the substrate to an electroplating process by flowing a current through a backside of the substrate to form a metal layer on the metal seed layer.

First claim

The invention claimed is:

1. A method for depositing a material on a substrate, comprising:
depositing a metal seed layer on an exposed silicon contact surface at a bottom of an aperture on a silicon substrate;
exposing a backside of the substrate to a potassium hydroxide solution while exposing the metal seed layer to a copper containing solution, wherein the substrate separates the potassium hydroxide solution from the copper containing solution; and
flowing a current through the substrate to form a metal layer on the metal seed layer.

2. The method of claim 1 , wherein flowing a current through the substrate to form a metal layer comprises filling the aperture with the metal layer.

3. The method of claim 1 , wherein the metal of the metal seed layer is selected from cobalt and nickel.

4. The method of claim 3 , wherein the metal of the metal seed layer is nickel deposited by an electroless process.

5. The method of claim 3 , wherein the metal of the metal seed layer is cobalt deposited by either an electroless or a chemical vapor deposition process.

6. The method of claim 1 , wherein the metal of the metal layer is copper.

7. A method for depositing a material on a substrate, comprising:
depositing a metal seed layer on an exposed silicon contact surface at the bottom of an aperture on a silicon substrate;
exposing a backside of the substrate to a hydrofluoric acid solution while exposing the metal seed layer to a copper containing solution, wherein the substrate separates the hydrofluoric acid solution from the copper containing solution; and
flowing a current through the substrate to form a metal layer on the metal seed layer.

8. A method for depositing a material on a substrate, comprising:
depositing a conformal barrier layer over a field region of a silicon substrate, at least one sidewall of a feature extending from the field region toward a backside of the silicon substrate and a bottom surface of the feature;
removing a portion of the conformal barrier layer from the bottom surface of the feature to expose the silicon substrate;
depositing a metal seed layer on the exposed silicon substrate at the bottom of the feature;
exposing the backside of the substrate to a contact solution while exposing the metal seed layer to a copper containing solution, wherein the substrate separates the contact solution from the copper containing solution; and
flowing a current through the silicon substrate to form a metal layer on the metal seed layer.

9. The method of claim 8 , further comprising forming an oxide containing layer over the field region of the silicon substrate prior to depositing a conformal barrier layer over the field region, the at least one sidewall, and the bottom surface of the feature.

10. The method of claim 8 , wherein the contact solution comprises a hydrofluoric acid solution.

11. The method of claim 10 , wherein the contact solution further comprises potassium fluoride.

12. The method of claim 8 , wherein the barrier layer comprises a tantalum nitride barrier layer.

13. The method of claim 12 , wherein the barrier layer further comprises a silicon dioxide layer and the silicon dioxide layer is positioned under the tantalum nitride barrier layer.

14. The method of claim 8 , wherein the contact solution comprises a potassium hydroxide solution.

Assignees

• Applied Materials Inc

Inventors

• Gouk Roman
• Verhaverbeke Steven

Classifications

• H10P14/47 Primary

  Electrolytic deposition, i.e. electroplating; Electroless plating · CPC title

• H10W20/036

  the barrier, adhesion or liner layers being within a main fill metal · CPC title

• H10W20/023

  the interconnections being through-semiconductor vias · CPC title

• H10W20/0245

  comprising use of blind vias during the manufacture · CPC title

• H10W20/0261

  characterised by the filling method or the material of the conductive fill · CPC title