Method and apparatus for electro-chemical mechanical deposition
View Patent ↗The present invention deposits a conductive material from an electrolyte solution to a predetermined area of a wafer. The steps that are used when making this application include applying the conductive material to the predetermined area of the wafer using an electrolyte solution disposed on a surface of the wafer, when the wafer is disposed between a cathode and an anode, and preventing accumulation of the conductive material to areas other than the predetermine area by mechanically polishing the other areas while the conductive material is being applied.
1. A method of polishing a conductive material from a top surface of a wafer using a pad, a solution and an electrode electrically coupled to the solution, wherein the top surface of the wafer further includes a cavity portion, comprising the steps of:
positioning the pad in close proximity to the top surface of the wafer;
applying the solution through the pad so that the solution is in contact with the top surface of the wafer;
applying a voltage between the top surface of the wafer and the electrode; and
polishing the conductive material using the pad to remove the conductive material from the top surface of the wafer, without substantially removing the conductive material within the cavity portion.
2. The method of claim 1 , wherein:
the polishing step includes the step of the pad touching the top surface of the wafer.
3. The method of claim 2 , wherein the pad is porous and wherein:
the applying step includes the step of introducing the solution through the porous pad.
4. The method of claim 2 , wherein the method further comprises the prior step of:
depositing the conductive material on the top surface of the wafer.
5. The method of claim 4 , wherein the solution includes a slurry.
6. The method of claim 2 , wherein:
the polishing step includes the step of moving the pad and the top surface of the wafer relative to one another.
7. An integrated circuit manufactured including the steps of claim 6 .
8. The method of claim 6 , wherein the solution includes a slurry.
9. The method of claim 2 , wherein:
the polishing step includes the step of moving the pad and the top surface of the wafer substantially linearly relative to one another.
10. The method of claim 2 , wherein the solution includes a slurry.
11. The method of claim 1 , wherein the pad is porous and wherein:
the applying step includes the step of introducing the solution through the porous pad.
12. The method of claim 11 , wherein the method further comprises the prior step of:
depositing the conductive material on the top surface of the wafer.
13. The method of claim 12 , wherein the conductive material is copper.
14. An integrated circuit manufactured including the steps of claim 11 .
15. The method of claim 1 , wherein the method further comprises the prior step of:
depositing the conductive material on the top surface of the wafer.
16. An integrated circuit manufactured including the steps of claim 1 .
17. The method of claim 1 , wherein:
the polishing step includes the step of pulsing the electric current at the top surface of the wafer.
18. The method of claim 1 , wherein the conductive material is copper.
19. A method of forming a conductive material on desired areas of a workpiece and preventing the accumulation of the conductive material on undesired areas of the workpiece using a pad, a solution and an electrode electrically coupled to the solution, comprising the steps of:
positioning the pad in close proximity to the workpiece;
applying the solution through the pad so that the solution is in contact with the workpiece;
applying a voltage between the workpiece and the electrode; and
forming the conductive material on the workpiece using the pad to prevent the accumulation of the conductive material on undesired areas of the workpiece.
20. The method of claim 19 , wherein:
the forming step includes the step of the pad touching the workpiece.
21. The method of claim 20 , wherein the pad is porous and wherein:
the applying step includes the step of introducing the solution through the porous pad.
22. The method of claim 20 , wherein:
the forming step includes the step of moving the pad and the workpiece relative to one another.
23. The method of claim 22 , wherein the solution includes a slurry.
24. An integrated circuit manufactured including the steps of claim 22 .
25. The method of claim 20 , wherein:
the forming step includes the step of moving the pad and the workpiece substantially linearly relative to one another.
26. The method of claim 20 , wherein the solution includes a slurry.
27. The method of claim 19 , wherein the forming step includes the steps of:
depositing the conductive material on the workpiece to fill predetermined features in the workpiece; and
polishing the conductive material on the workpiece using the pad to remove the conductive material from undesired areas of the workpiece.
28. The method of claim 27 , wherein:
during at least a portion of the depositing step, the step of applying a voltage between the workpiece and the electrode is performed at a first polarity; and
during at least a portion of the polishing step, the step of applying a voltage between the workpiece and the electrode is performed at a second polarity opposite the first polarity.
29. The method of claim 28 , wherein the pad is porous and wherein:
the applying step includes the step of introducing the solution through the porous pad.
30. The method of claim 27 , wherein the pad is porous and wherein:
the applying step includes the step of introducing the solution through the porous pad.
31. An integrated circuit manufactured including the steps of claim 27 .
32. The method of claim 19 , wherein the pad is porous and wherein:
the applying step includes the step of introducing the solution through the porous pad.
33. The method of claim 19 , wherein the method further comprises the prior step of:
depositing the conductive material on the workpiece to fill predetermined features in the workpiece.
34. The method of claim 33 , wherein the conductive material is copper.
35. An integrated circuit manufactured including the steps of claim 19 .
36. The method of claim 19 , wherein:
the forming step includes the step of the pulsing the electric current at the workpiece.
37. The method of claim 19 , wherein the conductive material is copper.