Processing system for detecting in-situ arcing events during substrate processing

• US 9,129,779 B2
• Filed: 04/06/2012
• Issued: 09/08/2015
• Est. Priority Date: 07/07/2008
• Status: Active Grant

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Booth, Jean-Paul, Keil, Douglas
• Primary Examiner(s): NGUYEN, HOAI AN D
• Application Number:
  US13/441,187
• Publication Number:
  US 20120259562A1
• Time in Patent Office: 1,250 Days
• Field of Search: 324/676, 324/658, 324/649, 324/600, 324/536, 361/2, 361/12, 361/14, 361/134, 219/121.11, 219/121.36, 219/121.43, 219/121.59
• US Class Current: 1/1
• CPC Class Codes: G01D 5/24 by varying capacitance
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• CPC Class Codes: G01R 31/1272 of cable, line or wire insulation, e.g. using partial discharge measurements locating faults in cables G01R31/083
• CPC Class Codes: G01R 31/34 Testing dynamo-electric machines
• CPC Class Codes: G01R 31/343 in operation
• CPC Class Codes: H01J 37/32935 Monitoring and controlling tubes by information coming from the object and/or discharge
• CPC Class Codes: H01J 37/3299 Feedback systems
• CPC Class Codes: H02H 1/0015 Using arc detectors
• CPC Class Codes: H02H 3/44 responsive to the rate of change of electrical quantities

Abstract

A processing system for detecting in-situ arcing events during substrate processing is provided. The processing systems includes at least a plasma processing chamber having a probe arrangement, wherein the probe arrangement is disposed on a surface of the processing chamber and is configured to measure at least one plasma processing parameter. The probe arrangement includes a plasma-facing sensor and a measuring capacitor, wherein the plasma-facing sensor is coupled to a first plate of the measuring capacitor. The probe arrangement also includes a detection arrangement that is coupled to a second plate of the measuring capacitor, wherein the detection arrangement is configured for converting an induced current flowing through the measuring capacitor into a set of digital signals, which is processed to detect the in-situ arcing events.

Claims

1. A processing system for detecting in-situ arcing events during substrate processing, comprising:

at least a plasma processing chamber having a probe arrangement, wherein said probe arrangement is disposed on a surface of said processing chamber and is configured to measure at least one plasma processing parameter, wherein said probe arrangement includes

a plasma-facing sensor, and

a measuring capacitor, wherein said plasma-facing sensor is coupled to a first plate of said measuring capacitor; and

a detection arrangement, said detection arrangement is coupled to a second plate of said measuring capacitor, wherein said detection arrangement is configured for converting an induced current flowing through said measuring capacitor into a set of digital signals, said set of digital signals being processed to detect said in-situ arcing events.

2. The processing system of claim 1 wherein said plasma-facing sensor is disposed in an upper electrode.

3. The processing system of claim 1 wherein said plasma-facing sensor is disposed on a chamber wall of said processing chamber.

4. The processing system of claim 1 wherein said plasma-facing sensor is made of a conductive material.

5. The processing system of claim 1 wherein said plasma-facing sensor is a capacitively-coupled electrostatic (CCE) probe head.

6. The processing system of claim 1 wherein said detection arrangement includes

a current-to-voltage converter, wherein said current-to-voltage converter is configured for at least converting said induced current flowing through said probe arrangement into a set of analog voltage signals,

an analog-to-digital converter configured for at least converting said set of analog voltage signals into said set of digital signals, and

a signal processor, wherein said signal processor is configured for at least processing said set of digital signals to detect high frequency perturbations, said high frequency perturbations indicating said in-situ arcing events.

7. The processing system of claim 6 wherein said high frequency perturbations have amplitude excursions in both a positive direction and a negative direction.

8. The processing system of claim 1 further including a tool control circuit, wherein said tool control circuit is configured for receiving a message from said detection arrangement when said in-situ arcing events are detected, said tool control circuit is configured to apply correction actions to fix said in-situ arcing events.

9. The processing system of claim 1 further including a voltage measurement device coupled to said first plate of said measuring capacitor, wherein said voltage measurement device being configured for at least collecting voltage measurements and for measuring potential change of said plasma-facing sensor.

10. The processing system of claim 9 wherein voltage measurements collected by said voltage measurement device is converted to a digital signal for signal processing to detect said in-situ arcing events.

11. A processing system for detecting in-situ arcing events within a processing chamber during substrate processing, comprising:

means for collecting a set of process data, said process data including induced current signals flowing through a measuring capacitor;

means for converting said induced current signals into a set of analog voltage signals;

means for converting said set of analog voltage signals into a set of digital signals; and

means for analyzing said set of digital signals to detect high frequency perturbations, said high frequency perturbations indicating said in-situ arcing events.

12. The processing system of claim 11 further includes means for comparing a rate of change of said induced current signals to a pre-defined threshold, wherein said in-situ arcing events exist if said rate of change is outside of said pre-defined threshold.

13. The processing system of claim 12 further includes means for sending a message to a tool controller circuit when said in-situ arcing events are detected, said tool control circuit is configured to apply correction actions to fix said in-situ arcing events.

14. The processing system of claim 11 further includes means for measuring voltage signals from a plasma-facing sensor to determine potential change during substrate processing.

15. The processing system of claim 14 further includes converting said measured voltage signals into digital signals.

16. The processing system of claim 15 further includes analyzing said digital signals to detect said high frequency perturbations, wherein said high frequency perturbations indicating said in-situ arcing events.

17. The processing system of claim 16 further includes comparing a rate of change of said voltage signals to a pre-defined threshold, wherein said in-situ arcing events exist if said rate of change is outside of said pre-defined threshold.

18. The processing system of claim 11 further includes means for applying a set of periodic radio frequency (RF) pulse trains to said measuring capacitor and measuring current decay signals of said measuring capacitor.

19. The processing system of claim 18 further includes applying an arc detection algorithm to detect said high frequency perturbations above a pre-defined threshold on said measuring capacitor'"'"'s current decay signals.

20. The processing system of claim 19 further includes comparing a rate of change of said current decay signals to a pre-defined threshold, wherein said in-situ arcing events exist if said rate of change is outside of said pre-defined threshold.