Methods and apparatuses for dynamically tunable wafer-edge electroplating

Patent metadata

Field	Value
Publication number	US-9752248-B2
Application number	US-201414578068-A
Country	US
Kind code	B2
Filing date	Dec 19, 2014
Priority date	Dec 19, 2014
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

Disclosed herein are methods of electroplating which may include placing a substrate, an anode, and an electroplating solution in an electroplating cell such that the substrate and the anode are located on opposite sides of a fluidically-permeable plate, setting the configuration of one or more seals which, when in their sealing configuration, substantially seal pores of the fluidically-permeable plate, and applying an electrical potential between the anode and the first substrate sufficient to cause electroplating on the first substrate such that the rate of electroplating in an edge region of the first substrate is affected by the configuration of the one or more seals. Also disclosed herein are apparatuses for electroplating which may include one or more seals for substantially sealing a subset of the pores in a fluidically-permeable plate whose sealing configuration affects a rate of electroplating in an edge region of the substrate.

First claim

We claim:

1. A method of electroplating one or more semiconductor substrates in an apparatus, wherein the apparatus comprises:
an electroplating cell;
a substrate holder configured to hold a substrate within the electroplating cell;
a fluidically-permeable plate located within the electroplating cell and oriented substantially parallel to the substrate held in the substrate holder, wherein the plate has multiple pores which, when immersed in electroplating solution, provide a fluidic connection between said electroplating solution on opposite sides of the plate;
a plurality of seals, wherein each seal is configured, when in its sealing configuration, to substantially seal a subset of the pores of the fluidically-permeable plate, the subset located in an edge region of the plate, wherein one or more seals of the plurality of seals are configured to be individually activated from a non-sealing configuration to the sealing configuration;
a power supply configured to apply an electrical potential between an anode in the electroplating cell and the substrate held by the substrate holder sufficient to cause electroplating on the substrate; and
a controller comprising a processor and a memory, the controller configured to set the configuration of the one or more seals of the plurality of seals;
wherein, during application of said electrical potential, the rate of electroplating in an edge region of the substrate is affected by the configuration of the one or more seals of the plurality of seals, wherein
the method comprises:
(a) setting the configuration of the one or more seals of the plurality of seals which, when in their sealing configuration, substantially seal the subset of the pores of the fluidically-permeable plate, the subset located in the edge region of the fluidically-permeable plate; and
(b) applying an electrical potential between the anode and the first substrate sufficient to cause electroplating on the first substrate, wherein the rate of electroplating in an edge region of the first substrate is affected by the configuration of the one or more seals.

2. The method of claim 1 , wherein the one or more seals of the plurality of seals, when in their sealing configuration, seal the subset of pores in the edge region of the fluidically-permeable plate by contacting the fluidically-permeable plate in the edge region.

3. The method of claim 2 , wherein the plurality of seals comprise two inflatable seals which, when in their sealing configuration, are inflated so as to contact the fluidically-permeable plate in the edge region, and wherein setting the configuration of the one or more seals comprises inflating and/or deflating the one or more of the seals.

4. The method of claim 1 , wherein the edge region of the first substrate is from the first substrate's edge to about 0.5 inches of its edge, and the edge region of the fluidically-permeable plate is from the plate's edge to about 2 inches of its edge.

5. The method of claim 4 , wherein the edge region of the fluidically-permeable plate has a greater average porosity than the average porosity over the other portions of the fluidically-permeable plate.

6. The method of claim 1 , further comprising:
adjusting the configuration of the one or more seals of the plurality of seals multiple times during the electroplating of the first substrate to vary the rate of electroplating in the edge region of the first substrate multiple times while electroplating the first substrate.

7. The method of claim 1 , further comprising:
(c) replacing the first substrate in the electroplating cell with a second substrate having a diameter significantly different than the diameter of the first substrate;
(d) adjusting the configuration of the one or more seals of the plurality of seals for the second substrate;
(e) applying an electrical potential between the anode and the second substrate sufficient to cause electroplating on the second substrate, wherein the rate of electroplating in an edge region of the second substrate is affected by the adjusted configuration of the one or more seals.

8. The method of claim 1 , wherein the anode comprises copper and the electroplating results in the deposition of copper on the first substrate.

9. An apparatus for electroplating one or more semiconductor substrates, the apparatus comprising:
an electroplating cell;
a substrate holder configured to hold a substrate within the electroplating cell;
a fluidically-permeable plate located within the electroplating cell and oriented substantially parallel to the substrate held in the substrate holder, wherein the fluidically-permeable plate has multiple pores which, when immersed in electroplating solution, provide a fluidic connection between said electroplating solution on opposite sides of the plate;
a plurality of seals, wherein each seal is configured, when in its sealing configuration, to substantially seal a subset of the pores of the fluidically-permeable plate, the subset located in an edge region of the plate, wherein one or more seals of the plurality of seals are configured to be individually activated from a non-sealing configuration to the sealing configuration;
a power supply configured to apply an electrical potential between an anode in the electroplating cell and the substrate held by the substrate holder sufficient to cause electroplating on the substrate; and
a controller comprising a processor and a memory, the controller configured to set the configuration of the one or more seals of the plurality of seals;

wherein, during application of said electrical potential, the rate of electroplating in an edge region of the substrate is affected by the configuration of the one or more seals of the plurality of seals.

10. The apparatus of claim 9 , wherein the one or more seals of the plurality of seals, when in their sealing configuration, seal the subset of pores in the edge region by contacting the fluidically-permeable plate in the edge region.

11. The apparatus of claim 10 , wherein the plurality of seals comprise two inflatable seals which, when in their sealing configuration, are inflated so as to contact the fluidically-permeable plate in the edge region.

12. The apparatus of claim 11 , wherein the two inflatable seals are substantially ring-shaped and oriented such that their center axes substantially align with the center axis of a substrate placed in the electroplating cell.

13. The apparatus of claim 12 , wherein the two inflatable ring-shaped seals each have a contact side configured to contact the fluidically-permeable plate when the seals are inflated in their sealing configuration, and wherein each of said contact sides has a radial width of between about 0.1 and 1 inch.

14. The apparatus of claim 13 , wherein each of said contact sides has a radial width of between about 0.2 and 0.4 inches.

15. The apparatus of claim 9 , wherein the edge region of the substrate is from the substrate's edge to about 0.5 inches of its edge, and the edge region of the fluidically-permeable plate is from the plate's edge to about 2 inches of its edge.

16. The apparatus of claim 15 , wherein the edge region of the fluidically-permeable plate has a greater average porosity than the average porosity over the other portions of the fluidically permeable plate.

17. The apparatus of claim 16 , wherein the edge region of the fluidically permeable plate has a greater average pore number density per unit area than the average over the other portions of the fluidically permeable plate.

18. The apparatus of claim 16 , wherei

Assignees

• Lam Res Corp

Inventors

• Kagajwala Burhanuddin
• Buckalew Bryan L
• Berke Aaron
• Fortner James Isaac
• Rash Robert

Classifications

• C25D17/001 Primary

  Apparatus specially adapted for electrolytic coating of wafers, e.g. semiconductors or solar cells · CPC title

• C25D17/002

  Cell separation, e.g. membranes, diaphragms · CPC title

• C25D5/022

  using masking means · CPC title