Process for forming a transition zone terminated superconformal filling

Patent metadata

Field	Value
Publication number	US-10508358-B2
Application number	US-201715489089-A
Country	US
Kind code	B2
Filing date	Apr 17, 2017
Priority date	Sep 17, 2012
Publication date	Dec 17, 2019
Grant date	Dec 17, 2019

Abstract

Forming a transition zone terminated superconformal filling in a recess includes: providing an electrodeposition composition including: a metal electrolyte including a plurality of metal ions, solvent, and suppressor; providing the article including: a field surface and the recess that includes a distal position and a proximate position; exposing the recess to the electrodeposition composition; potentiodynamically controlling an electric potential of the recess with a potential wave form; bifurcating the recess into an active metal deposition region and a passive region; forming a transition zone; decreasing the electric potential of the recess by the potential wave form; progressively moving the transition zone closer to the field surface and away from the distal position; and reducing the metal ions and depositing the metal in the active metal deposition region and not in the passive region to form the transition zone terminated superconformal filling in the recess of the substrate.

First claim

What is claimed is:

1. A process for forming a transition zone terminated superconformal filling in a recess of a substrate by electrodepositing metal, the process comprising:
providing an electrodeposition composition comprising:
a metal electrolyte comprising a plurality of metal ions and a solvent; and
a suppressor disposed in the solvent;

providing the substrate comprising:
a field surface; and
the recess disposed in the substrate, the recess comprising a distal position and a proximate position relative to the field surface of the substrate;

exposing the recess to the electrodeposition composition;
potentiodynamically controlling an electric potential of the recess with a potential wave form;
bifurcating the recess into an active metal deposition region and a passive region in response to potentiodynamically controlling the electric potential;
forming, in response to bifurcating the recess, a transition zone at an interface of the active metal deposition region and the passive region;
decreasing the electric potential of the recess by the potential wave form;
progressively moving the transition zone closer to the field surface and away from the distal position in response to decreasing the electric potential; and
reducing the metal ions to form metal and depositing the metal in the active metal deposition region and not in the passive region to form the transition zone terminated superconformal filling in the recess of the substrate, the transition zone terminated superconformal filling being:
void-free,
disposed in the recess in the active metal deposition region from the distal position to the transition zone,
comprising a v-notch, and
absent in the passive region between the proximate position and the transition zone,

wherein the electrodeposition composition has an S-shaped negative differential resistance cyclic voltammogram.

2. The process of claim 1 , further comprising wherein the transition zone terminated superconformal filling is absent on the field surface.

3. The process of claim 1 , further comprising:
terminating the depositing the metal before completely filling the recess to the field surface.

4. The process of claim 1 , further comprising:
terminating depositing the metal after completely filling the recess to the field surface.

5. The process of claim 1 , wherein the metal ions comprise Co 2+ , Ni 2+ , Fe 2+ , Au 3+ , Ag + , Zn 2+ , Sn 2+ , Pb 2+ , or a combination comprising at least one of the foregoing metal ions.

6. The process of claim 1 , wherein the electrodeposition composition further comprises anions for the metal ions, the anions comprising sulfate, chloride, sulfite, or a combination comprising at least one of the foregoing anions.

7. The process of claim 5 , wherein the metal comprises cobalt, iron, nickel, gold, lead, tin, or a combination comprising at least one of the foregoing metals.

8. The process of claim 1 , wherein the suppressor comprises a polyethyleneimine, a phenolphthalein, a polyether, benzimidazole and its derivatives, or a combination comprising at least one of the foregoing suppressors.

9. The process of claim 1 , wherein the solvent comprises water, an alcohol, or a combination comprising at least one of the foregoing solvents.

10. The process of claim 1 , wherein the recess comprises:
a depth from the field surface to the distal position that is from 10 nm to 900 μm, and
an aspect ratio from 1 to 50.

11. The process of claim 1 , wherein the recess comprises a through hole, a blind hole, or a combination comprising at least one of the foregoing recesses.

12. The process of claim 1 , wherein the potential wave form comprises a potential-step wave form comprising:
a first potential with a first dwell time; and
a second potential with a second dwell time,
wherein the second potential is more negative than the first potential.

13. The process of claim 12 , wherein the first dwell time is longer than the second dwell time.

14. The process of claim 1 , wherein the potential wave form comprises a potential ramp.

15. The process of claim 14 , wherein the potential ramp comprises a plurality of ramp rates.

16. A process for forming a transition zone terminated superconformal filling in a recess of a substrate by electrodepositing metal, the process comprising:
providing an electrodeposition composition comprising:
a metal electrolyte comprising a plurality of metal ions and a solvent; and
a suppressor disposed in the solvent;

providing the substrate comprising:
a field surface; and
the recess disposed in the substrate, the recess comprising a distal position and a proximate position relative to the field surface of the substrate;

exposing the recess to the electrodeposition composition;
galvanodynamically controlling an electric current between the recess and a counter electrode with a current wave form;
bifurcating the recess into an active metal deposition region and a passive region in response to galvanodynamically controlling the electric current;
forming, in response to bifurcating the recess, a transition zone at an interface of the active metal deposition region and the passive region;
changing the electric current at the recess by the current wave form;
progressively moving the transition zone closer to the field surface and away from the distal position in response to changing the electric current; and
reducing the metal ions to form metal and depositing the metal in the active metal deposition region and not in the passive region to form the transition zone terminated superconformal filling in the recess of the substrate, the transition zone terminated superconformal filling being:
void-free,
disposed in the recess in the active metal deposition region from the distal position to the transition zone,
comprising a v-notch, and
absent in the passive region between the proximate position and the transition zone,
wherein the electrodeposition composition has an S-shaped negative differential resistance cyclic voltammogram.

17. The process of claim 16 , wherein the metal ions comprise Co 2+ , Ni 2+ , Fe 2+ , Au 3+ , Ag + , Sn 2+ , Pb 2+ or a combination comprising at least one of the foregoing metal ions, and
the metal comprises cobalt, gold, nickel, or a combination comprising at least one of the foregoing metals.

18. The process of claim 16 , wherein the current wave form comprises a current ramp wave form.

Assignees

• Government Of The Us Secretary Of Commerce

Inventors

• Josell Daniel
• Moffat Thomas P

Classifications

• 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

• H10P14/47

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

• H10W20/056

  by filling conductive material into holes, grooves or trenches · CPC title

• H10W20/023

  the interconnections being through-semiconductor vias · CPC title