Semiconductor reflow processing for high aspect ratio fill

Patent metadata

Field	Value
Publication number	US-9245798-B2
Application number	US-201313801860-A
Country	US
Kind code	B2
Filing date	Mar 13, 2013
Priority date	Apr 26, 2012
Publication date	Jan 26, 2016
Grant date	Jan 26, 2016

Abstract

A method for at least partially filling a feature on a workpiece includes obtaining a workpiece including a feature having a high aspect ratio in the range of about 10 to about 80, depositing a first conformal conductive layer in the feature, and thermally treating the workpiece to reflow the first conformal conductive layer in the feature.

First claim

The invention claimed is:

1. A method for at least partially filling a feature on a workpiece, the method comprising:
(a) obtaining a workpiece including a feature having a high aspect ratio in the range of about 10 to about 80;
(b) electrochemically depositing a first conformal conductive layer in the feature;
(c) thermally treating the workpiece to reflow the first conformal conductive layer into the feature in a temperature range of about 250° C. to about 350° C. so as to at least partially fill the feature with a reflowed conductive layer;
(d) electrochemically depositing a second conformal conductive layer after the reflowed first conformal conductive layer; and
(e) thermally treating the workpiece to reflow the second conformal conductive layer into the feature.

2. The method of claim 1 , wherein thermally treating the workpiece reduces voids in the feature fill.

3. The method of claim 1 , further comprising depositing a barrier layer in the feature before the first conformal conductive layer is deposited.

4. The method of claim 3 , wherein the first conformal conductive layer is deposited directly on the barrier layer.

5. The method of claim 1 , further comprising depositing a conductive seed layer in the feature before the first conformal conductive layer is deposited.

6. The method of claim 5 , wherein metal for the seed layer is selected from the group consisting of copper, cobalt, nickel, gold, silver, manganese, tin, aluminum, ruthenium, and alloys thereof.

7. The method of claim 5 , wherein the seed layer is selected from the group consisting of seed, secondary seed, and a stack film of seed and liner.

8. The method of claim 1 , wherein metal for the first conformal conductive layer is selected from the group consisting of copper, cobalt, nickel, gold, silver, manganese, tin, aluminum, and alloys thereof.

9. The method of claim 1 , further comprising depositing a third conformal conductive layer after the reflowed second conformal conductive layer and thermally treating the workpiece to reflow the third conformal conductive layer.

10. The method of claim 1 , wherein the reflowed second conformal conductive layer either partially or completely fills the feature.

11. The method of claim 1 , wherein the first conformal conductive layer is deposited using a chemistry including at least one copper complex selected from the group consisting of copper ethylenediamine, citrate, tartrate, and urea.

12. The method of claim 1 , further comprising depositing a cap layer on the reflowed first conformal conductive layer.

13. The method of claim 12 , wherein the cap layer is deposited in an acidic chemistry.

14. The method of claim 1 , wherein the feature has an opening size selected from the group consisting of in the range of about 0.5 micron to about 15 microns, in the range of about 0.5 micron to about 10 microns, or in the range of about 0.5 micron to about 2 microns.

15. A method for at least partially filling a feature on a workpiece, the method comprising:
(a) obtaining a workpiece including a feature having a high aspect ratio in the range of about 10 to about 80;
(b) depositing a barrier layer in the feature;
(c) depositing a seed layer after the barrier layer;
(d) electrochemically depositing a first conformal conductive layer into the feature after the seed layer so as to at least partially fill the feature with a reflowed conductive layer;
(e) annealing the workpiece to reflow the first conductive layer in the feature and provide a reflowed first conformal conductive layer;
(f) electrochemically depositing a second conformal conductive layer after the reflowed first conformal conductive layer; and
(g) thermally treating the workpiece to reflow the second conformal conductive layer into the feature.

16. A method for at least partially filling a feature on a workpiece, the method comprising:
(a) obtaining a workpiece including a feature having a high aspect ratio in the range of about 10 to about 80, the feature including a barrier layer and a seed layer;
(b) electrochemically depositing a first conformal conductive layer in the feature after the seed layer; and
(c) annealing the workpiece to reflow the first conductive layer into the feature and provide a reflowed first conformal conductive layer so as to at least partially fill the feature with a reflowed conductive layer;
(d) electrochemically depositing a second conformal conductive layer after the reflowed first conformal conductive layer; and
(e) thermally treating the workpiece to reflow the second conformal conductive layer into the feature.

Assignees

• Applied Materials Inc
• Applied Matrials Inc

Inventors

• Emesh Ismail T
• Linke Robert C

Classifications

• H10W20/0261

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

• H10W20/0425

  comprising multiple stacked seed or nucleation layers · CPC title

• H10P95/00

  Generic processes or apparatus for manufacture or treatments not covered by the other groups of this subclass · CPC title

• H10W20/023

  the interconnections being through-semiconductor vias · CPC title

• H10W20/043

  for electroplating · CPC title