System and methods for measuring chemical concentrations of a plating solution

• US 20070026529A1
• Filed: 07/26/2005
• Published: 02/01/2007
• Est. Priority Date: 07/26/2005
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Hoermann, Alexander, Rabinovich, Yevgeniy, Ta, Kathryn
• Granted Patent: US 7,851,222 B2
• Time in Patent Office: Days
• US Class Current: 436/149
• CPC Class Codes: C25D 17/001 Apparatus specially adapted for electrolytic coating of wafers, e.g. semiconductors or solar cells
• CPC Class Codes: C25D 21/12 Process control or regulation controlling or regulating in general G05
• CPC Class Codes: Y10T 436/118339 with formation of a segmented stream
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

An electrochemical plating system, which includes one or more plating cell reservoirs for storing plating solution and a chemical analyzer in fluidic communication with the one or more plating cell reservoirs. The chemical analyzer is configured to measure chemical concentrations of the plating solution. The plating system further includes a plumbing system configured to facilitate the fluidic communication between the one or more plating cell reservoirs and the chemical analyzer and to substantially isolate the chemical analyzer from electrical noise generated by one or more plating cells of the one or more plating cell reservoirs.

Claims

1. An electrochemical plating system, comprising:

one or more plating cell reservoirs for storing plating solution;

a chemical analyzer in fluidic communication with the one or more plating cell reservoirs, wherein the chemical analyzer is configured to measure chemical concentrations of the plating solution; and

a plumbing system configured to facilitate the fluidic communication between the one or more plating cell reservoirs and the chemical analyzer and to substantially isolate the chemical analyzer from electrical noise generated by one or more plating cells of the one or more plating cell reservoirs.

2. The system of claim 1, further comprising a sampling reservoir coupled to the chemical analyzer, wherein the sampling reservoir is configured to hold a portion of the plating solution.

3. The system of claim 2, wherein the plumbing system comprises a first flow path for delivering the portion of the plating solution from the one or more plating cell reservoirs to the sampling reservoir.

4. The system of claim 2, wherein the plumbing system comprises a second flow path for circulating the portion of the plating solution through the chemical analyzer.

5. The system of claim 2, wherein the plumbing system comprises at least one valve that allows the portion of the plating solution to flow from the one or more plating cell reservoirs to the sampling reservoir, when the at least one valve is in an open position.

6. The system of claim 5, wherein the at least one valve is switched to a closed position once the sampling reservoir is filled with the portion of the plating solution to substantially isolate the chemical analyzer from the electrical noise.

7. The system of claim 2, wherein the plumbing system comprises a third flow path for returning the portion of the plating solution to the one or more plating cell reservoirs.

8. The system of claim 7, wherein the third flow path is used following the completion of the measurement of chemical concentrations in the portion of the plating solution.

9. The system of claim 2, wherein the plumbing system comprises a fourth flow path for draining liquid from the sampling reservoir out of the plumbing system.

10. The system of claim 9, wherein the fourth flow path is used for discarding one of de-ionized water and standard solution.

11. The system of claim 2, further comprising a temperature controller for maintaining the temperature of liquid inside the sampling reservoir within a predetermined range.

12. The system of claim 11, wherein the predetermined range is from about 18 degrees Celsius to about 22 degrees Celsius.

13. The system of claim 2, further comprising a temperature controller for maintaining the temperature of liquid inside the sampling reservoir at about 20 degrees Celsius.

14. The system of claim 1, wherein the electrical noise is generated by application of voltage in the one or more plating cells.

15. A method for measuring chemical concentrations of a plating solution, comprising:

delivering a portion of the plating solution from one or more plating cell reservoirs to a sampling reservoir;

circulating the portion of the plating solution through a chemical analyzer; and

isolating fluidic communication between the one or more plating cell reservoirs and the chemical analyzer.

16. The method of claim 15, wherein isolating the fluidic communication comprises closing at least one valve that allows the portion of the plating solution to flow from the one or more plating cell reservoirs to the sampling reservoir.

17. The method of claim 16, wherein the at least one valve is closed after the sampling reservoir is filled with the portion of the plating solution.

18. The method of claim 16, further comprising measuring chemical concentrations of the portion of the plating solution.

19. The method of claim 18, further comprising returning the portion of the plating solution to the one or more plating cell reservoirs after the chemical concentrations are measured.

20. The method of claim 18, further comprising maintaining the temperature of the portion of the plating solution inside the sampling reservoir at a predetermined range of temperatures.

21. The method of claim 18, wherein the predetermined range is from about 18 degrees Celsius to about 22 degrees Celsius.