Process monitoring apparatus and method

• US 6,652,710 B2
• Filed: 06/01/1999
• Issued: 11/25/2003
• Est. Priority Date: 05/12/1997
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Cruse, James P.
• Primary Examiner(s): Mills, Gregory
• Assistant Examiner(s): MacArthur, Sylvia
• Application Number:
  US09/322,912
• Publication Number:
  US 20010051437A1
• Time in Patent Office: 1,638 Days
• Field of Search: 156/345, 364/468.01, 364/468.28
• US Class Current: 156/345.48
• CPC Class Codes: B24B 37/013 Devices or means for detecting lapping completion
• CPC Class Codes: B81C 1/00587 Processes for avoiding or controlling over-etching not provided for in B81C1/00571 - B81C1/00579
• CPC Class Codes: B81C 2201/0132 Dry etching, i.e. plasma etching, barrel etching, reactive ion etching [RIE], sputter etching or ion milling
• CPC Class Codes: B81C 2201/0138 Monitoring physical parameters in the etching chamber, e.g. pressure, temperature or gas composition
• CPC Class Codes: B81C 99/0065 Process control; Yield prediction
• CPC Class Codes: H01J 37/32963 End-point detection
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps
• CPC Class Codes: H01L 22/26 Acting in response to an ongoing measurement without interruption of processing, e.g. endpoint detection, in-situ thickness measurement endpoint detection arrangements in CMP apparatus B24B37/013, in discharge apparatus H01J37/32
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

An apparatus capable of processing a wafer, comprises a chamber adapted to process the wafer, whereby one or more parameters of the process being conducted in the chamber may change during processing of the wafer; and a signal analyzer adapted to receive a plurality of input signals relating to the parameters and provide an output signal in relation to the input signals.

Claims

1. An apparatus capable of processing a wafer in a plasma, the apparatus comprising:

(a) a chamber to process the wafer in the plasma, whereby one or more parameters of a process being conducted in the chamber may change during processing of the wafer in the plasma; and

(b) a signal analyzer to receive a first input signal of a magnitude of a first parameter detected during processing of the wafer and a second input signal of a magnitude of a second parameter detected during processing of the wafer, the second parameter being a different parameter than the first parameter, and determine an output signal in relation to the first and second input signals during processing of the wafer in the plasma, the output signal being determinative of completion of the process.

2. An apparatus according to claim 1 wherein the signal analyzer provides an output signal determined from a mathematical calculation using the input signals, or by correlating the input signals to one another or to other values.

3. An apparatus according to claim 1 wherein the signal analyzer provides an output signal determined from a non-linear mathematical calculation performed on the input signals.

4. An apparatus according to claim 1 wherein the signal analyzer receives an input signal relating to a non-optical parameter and determines an output signal in relation to the non optical parameter.

5. An apparatus according to claim 1 wherein the signal analyzer receives an input signal comprising one or more of a reflected power data, tuning voltage data, chamber pressure data, foreline pressure data, temperature data, or gas composition data.

6. An apparatus according to claim 1 wherein an input signal to the signal analyzer is provided by one or more of a temperature sensor, a chamber pressure sensor, a foreline pressure sensor, a gas analyzer, an RF power supply, or a system controller.

7. An apparatus according to claim 1 wherein a system controller receives the output signal from the signal analyzer, and controls a process variable of the process chamber in relation to the output signal to end an etching process or to initiate a cleaning process.

8. An apparatus according to claim 1 wherein the signal analyzer comprises a general purpose computer.

9. An apparatus for monitoring a wafer processing system to process a wafer in a plasma and having multiple parameters, the apparatus comprising:

a signal analyzer to receive a first input signal of a magnitude of a first parameter detected during processing of the wafer in the plasma and a second input signal of a magnitude of a second parameter detected during processing of the wafer, the first and second parameters not being determined from one another and correlate the input signals to one another or to stored values to determine an output signal, the output signal being determinative of completion of processing of the wafer.

10. An apparatus according to claim 9 wherein the signal analyzer correlates the input signals by performing a mathematical calculation on the input signals, relating the input signals to one another, or relating the input signals to the stored values.

11. An apparatus according to claim 9 wherein the signal analyzer provides an output signal determined from a non-linear mathematical calculation performed on the input signals.

12. An apparatus according to claim 9 wherein the signal analyzer receives an input signal relating to a non-optical parameter and determines an output signal in relation to the non-optical parameter.

13. An apparatus according to claim 12 wherein the signal analyzer determines an output signal indicative of a state of processing of the wafer, a condition of the process chamber, or a state of the plasma in the process chamber.

14. An apparatus according to claim 9 wherein an input signal to the signal analyzer is provided by one or more of the following:

a temperature sensor, a chamber pressure sensor, a foreline pressure sensor, a gas analyzer, an RF power supply, or a system controller.

15. An apparatus capable of processing a wafer in a plasma, the apparatus comprising:

(a) a chamber to process the wafer in the plasma, whereby one or more non-optical parameters of a process being conducted in the chamber may change during processing of the wafer in the plasma; and

(b) a signal analyzer to receive a first input signal of a magnitude of an optical parameter detected during processing of the wafer and a second input signal of a magnitude of a non-optical parameter detected during processing of the wafer, and determine an output signal in relation to the first and second input signals during processing of the wafer in the plasma, the output signal being determinative of completion of the process.

16. An apparatus according to claim 15 wherein the signal analyzer correlates the input signals by performing a mathematical calculation on the input signals, or correlating the input signals to one another or other values.

17. An apparatus according to claim 15 wherein the signal analyzer provides an output signal determined from a non-linear mathematical calculation performed on the input signals.

18. An apparatus according to claim 15 wherein the signal analyzer determines an output signal indicative of a state of processing of the wafer, a condition of the process chamber, or a state of the plasma in the process chamber.

19. An apparatus according to claim 15 wherein an input signal to the signal analyzer is provided by one or more of the following:

a temperature sensor, a chamber pressure sensor, a foreline pressure sensor, a gas analyzer, an RF power supply, or a system controller.

20. An apparatus for processing a wafer in a plasma in a chamber, the apparatus comprising:

(a) a chamber to process the wafer in the plasma;

(b) a first sensor that detects first parametric data of a process being conducted in the chamber and a second sensor that detects second parametric data of a process being conducted in the chamber, and

(c) a signal analyzer to receive a first input signal of a magnitude of the first parametric data and a second input signal of a magnitude of the second parametric data detected by the first and second sensors during processing of the wafer in the plasma, the second parametric data being different parametric data than the first parametric data, determine an output signal by correlating the first input signal and second input signal, and compare the output signal to a threshold value to determine completion of the process.

21. An apparatus according to claim 20 wherein the signal analyzer correlates the input signals by performing a mathematical calculation on the input signals, or correlating the input signals to one another or other values.

22. An apparatus according to claim 20 wherein the signal analyzer provides an output signal determined from a non-linear mathematical calculation performed on the input signals.

23. An apparatus according to claim 20 wherein the signal analyzer determines an output signal indicative of a state of processing of the wafer, a condition of the process chamber, or a state of the plasma in the process chamber.

24. An apparatus according to claim 20 wherein the parametric data of the process being conducted in the chamber comprises one or more of a reflected power data, tuning voltage data, chamber pressure data, foreline pressure data, temperature data, or gas composition date.

25. An apparatus capable of analyzing processing of a wafer in a plasma in a processing system, the apparatus comprising:

(a) a first sensor to detect a magnitude of first parametric data of a process being conducted in the processing system and a second sensor adapted to detect a magnitude of second parametric data of the process, the second parametric data being different parametric data than the first parametric data; and

(b) a signal analyzer to acquire the parametric data during processing of the wafer in the plasma, determine an output signal by correlating the first parametric data and second parametric data, and compare the output signal to a threshold value to determine completion of processing of the wafer.

26. An apparatus according to claim 25 wherein the signal analyzer correlates the parametric data by performing a mathematical calculation on the parametric data, or correlating the parametric data to itself or other values.

27. An apparatus according to claim 25 wherein the signal analyzer provides an output signal determined from a non-linear mathematical calculation performed on the parametric data.

28. An apparatus according to claim 25 wherein the signal analyzer determines an output signal indicative of a state of processing of the wafer, a condition of the process chamber, or a state of the plasma of the processing system.

29. An apparatus according to claim 25 wherein the parametric data comprises one or more of a reflected power data, tuning voltage data, chamber pressure data, foreline pressure data, temperature data, or gas composition data.

30. An apparatus capable of processing a wafer, the apparatus comprising:

(a) a chamber comprising (i) a support pedestal capable of receiving the wafer, (ii) a gas manifold to introduce a process gas into the chamber, and (iii) a RF power supply to apply RF power to the support pedestal to form a plasma from the process gas to process the wafer, and to generate a first input signal of a magnitude of a RF parameter generated during a process being conducted in the chamber;

(b) an optical detector to detect a magnitude of an optical emissia generated by the plasma during the process and generate a second input signal of the magnitude of the detected optical emissia; and

(c) a signal analyzer to receive the first input signal and second input signal and determine an output signal in relation to the first and second input signals during processing of the wafer, the output signal being determinative or completion of the process.

31. An apparatus according to claim 30, wherein the signal analyzer provides an output signal determined from a mathematical calculation using the input signals, or by correlating the input signals to one another or to other values.

32. An apparatus according to claim 30, wherein the signal analyzer is adapted to determine an output signal determinative of an endpoint of an etching process.

33. An apparatus according to claim 30, wherein the signal an analyzer is adapted to determine an output signal determinative of completion of processing of a plurality of wafers.

34. An apparatus according to claim 33, wherein the signal analyzer is adapted to determine when cleaning of the chamber is required.

35. An apparatus according to claim 30 wherein the RF power supply is adapted to generate a first input signal in relation to a reflected power generated during the process.

36. An apparatus according to claim 30 wherein the RF power supply is adapted to generate a first input signal in relation to a tuning voltage generated during the process.

37. An apparatus according to claim 30 further comprising a pressure sensor adapted to detect a pressure in the chamber or in a foreline of the chamber and generate a third input signal in relation to the detected pressure, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

38. An apparatus according to claim 30 further comprising a temperature sensor adapted to detect a temperature in the chamber and generate a third input signal in relation to the detected temperature, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

39. An apparatus according to claim 36 further comprising a gas sensor adapted to detect a gas in the chamber or in a foreline of the chamber and generate a third input signal in relation to the detected gas, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

40. An apparatus capable of processing a wafer, the apparatus comprising:

(a) a chamber comprising (i) a support pedestal capable of receiving the wafer, (ii) a gas manifold to introduce a process gas into the chamber, and (iii) a RF power supply to apply RF power to the support pedestal to form a plasma from the process gas to process the wafer;

(b) an optical detector to detect a magnitude of an optical emissia generated by the plasma during a process and generate a first input signal of the magnitude of the detected optical emissia;

(c) a pressure sensor to detect a magnitude of a pressure in the chamber or in a foreline of the chamber during the process and generate a second input signal of the magnitude of the detected pressure; and

(d) a signal analyzer to receive the first input signal and second input signal and determine an output signal in relation to the first and second input signals during processing of the wafer, the output signal being determinative of completion of the process.

41. An apparatus according to claim 40 wherein the signal analyzer provides an output signal determined from a mathematical calculation using the input signals, or by correlating the input signals to one another or to other values.

42. An apparatus according to claim 40 wherein the signal analyzer is adapted to determine an output signal determinative of an endpoint of an etching process.

43. An apparatus according to claim 40 wherein the signal analyzer is adapted to determine an output signal determinative of completion of processing at a plurality of wafers.

44. An apparatus according to claim 43 wherein the signal analyzer is adapted to determine when cleaning of the chamber is required.

45. An apparatus according to claim 40 wherein the RF power supply is adapted to generate a third input signal in relation to a RF parameter generated during the process, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

46. An apparatus according to claim 45 wherein the RF power supply is adapted to generate a third input signal in relation to a reflected power generated during the process.

47. An apparatus according to claim 45 wherein the RF power supply is adapted to generate a third input signal in relation to a tuning voltage generated during the process.

48. An apparatus according to claim 40 further comprising a temperature sensor adapted to detect a temperature in the chamber and generate a third input signal in relation to the detected temperature, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

49. An apparatus according to claim 40 further comprising a gas sensor adapted to detect a gas in the chamber or foreline and generate a third input signal in relation to the detected gas, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

50. An apparatus capable of processing a wafer, the apparatus comprising:

(a) a chamber comprising (i) a support pedestal capable of receiving the wafer, (ii) a gas manifold to introduce a process gas into the chamber, and (iii) a RF power supply to apply a RF power to the support pedestal to form a plasma from the process gas to process the wafer;

(b) an optical detector to detect a magnitude of an optical emissia generated by the plasma during a process and generate a first input signal of the magnitude of the detected optical emissia;

(c) a temperature sensor to detect a magnitude of a temperature in the chamber during the process and generate a second input signal of the magnitude of the detected temperature; and

(d) a signal analyzer to receive the first input signal and second input signal and determine an output signal in relation to the first and second input signals during processing of the wafer, the output signal being determinative of completion of the process.

51. An apparatus according to claim 50 wherein the signal analyzer provides an output signal determined from a mathematical calculation using the input signals, or by correlating the input signals to one another or to other values.

52. An apparatus according to claim 50 wherein the signal analyzer is adapted to determine an output signal determinative of an endpoint of an etching process.

53. An apparatus according to claim 50 wherein the signal analyzer is adapted to determine an output signal determinative of completion of processing of a plurality of wafers.

54. An apparatus according to claim 53 wherein the signal analyzer is adapted to determine when cleaning of the chamber is required.

55. An apparatus according to claim 50 wherein the RF power supply is adapted to generate a third input signal in relation to a RF parameter generated during the process, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

56. An apparatus according to claim 55 wherein the RF power supply is adapted to generate a third input signal in relation to a reflected power generated during the process.

57. An apparatus according to claim 55 wherein the RF power supply is adapted to generate a third input signal in relation to a tuning voltage generated during the process.

58. An apparatus according to claim 50 further comprising a pressure sensor adapted to detect a pressure in the chamber or in a foreline of the chamber and generate a third input signal in relation to the detected pressure, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

59. An apparatus according to claim 50 further comprising a gas sensor adapted to detect a gas in the chamber or in a foreline of the chamber and generate a third input signal in relation to the detected gas, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

60. An apparatus capable of processing a wafer, the apparatus comprising:

(a) a chamber comprising (i) a support pedestal capable of receiving the wafer, (ii) a gas manifold to introduce a gas into the chamber, and (iii) a RF power supply to apply a RF power to the support pedestal to form a plasma from the gas to process the wafer;

(b) an optical detector to detect a magnitude of an optical emissia generated by the plasma during a process and generate a first input signal of the magnitude of the detected optical emissia;

(c) a gas sensor to detect a magnitude of the gas in the chamber or in a foreline of the chamber during the process and generate a second input signal of the magnitude of the detected gas; and

(d) a signal analyzer to receive the first input signal and second input signal and determine an output signal in relation to the first and second input signals during processing of the wafer, the output signal being determinative of completion of the process.

61. An apparatus according to claim 60 wherein the signal analyzer provides an output signal determined from a mathematical calculation using the input signals, or by correlating the input signals to one another or to other values.

62. An apparatus according to claim 60 wherein the signal analyzer is adapted to determine an output signal determinative of an endpoint of an etching process.

63. An apparatus according to claim 60 wherein the signal analyzer is adapted to determine an output signal determinative of completion of processing of a plurality of wafers.

64. An apparatus according to claim 63 wherein the signal analyzer is adapted to determine when cleaning of the chamber is required.

65. An apparatus according to claim 60 wherein the RF power supply is adapted to generate a third input signal in relation to a RF parameter generated during the process, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

66. An apparatus according to claim 65 wherein the RF power supply is adapted to generate a third input signal in relation to a reflected power generated during the process.

67. An apparatus according to claim 65 wherein the RF power supply is adapted to generate a third input signal in relation to a tuning voltage generated during the process.

68. An apparatus according to claim 60 further comprising a pressure sensor adapted to detect a pressure in the chamber or the foreline and generate a third input signal in relation to the detected pressure, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

69. An apparatus according to claim 65 further comprising a temperature sensor adapted to detect a temperature in the chamber and generate a third input signal in relation to the detected temperature, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

70. An apparatus capable of processing a wafer, the apparatus comprising:

(a) a chamber comprising (i) a support pedestal capable of receiving the wafer, (ii) a gas manifold to introduce a process gas into the chamber, and (iii) a RF power supply to apply RF power to the support pedestal to form a plasma from the process gas to process the wafer and generate a first input signal of a magnitude of a RF parameter generated during a process being conducted in the chamber;

(b) a pressure sensor to detect a magnitude of a pressure in the chamber during the process and generate a second input signal of the magnitude of the detected pressure; and

(c) a signal analyzer to receive the first input signal and second input signal and determine an output signal in relation to the first and second input signals during processing of the wafer, the output signal being determinative of completion of the process.

71. An apparatus according to claim 70 wherein the signal analyzer provides an output signal determined from a mathematical calculation using the input signals, or by correlating the input signals to one another or to other values.

72. An apparatus according to claim 70 wherein the signal analyzer is adapted to determine an output signal determinative of an endpoint of an etching process.

73. An apparatus according to claim 70 wherein the signal analyzer is adapted to determine an output signal determinative of completion of processing of a plurality of wafers.

74. An apparatus according to claim 73 wherein the signal analyzer is adapted to determine when cleaning of the chamber is required.

75. An apparatus according to claim 70 wherein the RF power supply is adapted to generate a first input signal in relation to a reflected power generated during the process.

76. An apparatus according to claim 70 wherein the RF power supply is adapted to generate a first input signal in relation to a tuning voltage generated during the process.

77. An apparatus according to claim 70 further comprising an optical detector adapted to detect optical emissia generated by the plasma in the chamber during the process and generate a third input signal in relation to the detected optical emissia, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

78. An apparatus according to claim 70 further comprising a pressure sensor adapted to detect a pressure in the chamber or in a foreline of the chamber during the process and generate a third input signal in relation to the detected pressure, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

79. An apparatus according to claim 70 further comprising a temperature sensor adapted to detect a temperature in the chamber during the process and generate a third input signal in relation to the detected temperature, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

80. An apparatus according to claim 70 further comprising a gas sensor adapted to detect a gas in the chamber or in a foreline of the chamber during the process and generate a third input signal in relation to the detected gas, and wherein the signal analyzer is further adapted to receive the third input signal and determine the output signal in relation to the first input signal, second input signal and third input signal.

81. An apparatus capable of processing a wafer, the apparatus comprising:

(a) a chamber comprising (i) a support pedestal capable of receiving the wafer, (ii) a gas manifold to introduce a process gas into the chamber, and (iii) a RF power supply to apply RF power to the support pedestal to form a plasma from the process gas to process the wafer, whereby one or more non optical parameters of a process being conducted in the chamber may change during processing of the wafer; and

(b) a signal analyzer to receive a first input signal of a magnitude of a first non-optical parameter detected during the process and a second input signal of a magnitude of a second non-optical parameter detected during the process, the second non-optical parameter being a different parameter than the first non-optical parameter, and determine an output signal in relation to the first and second input signals during processing of the wafer, the output signal being determinative of completion of the process.

82. An apparatus according to claim 81 wherein the signal analyzer correlates the input signals by performing a mathematical calculation on the input signals, or correlating the input signals to one another or other values.

83. An apparatus according to claim 82 wherein the signal analyzer provides an output signal determined from a non-linear mathematical calculation performed on the input signals.

84. An apparatus according to claim 81 wherein the signal analyzer is adapted to determine an output signal determinative of an endpoint of an etching process.

85. An apparatus according to claim 81 wherein the signal analyzer is adapted to determine an output signal determinative of completion of processing of a plurality of wafers.

86. An apparatus according to claim 85 wherein the signal analyzer is adapted to determine when cleaning of the chamber is required.

87. An apparatus according to claim 81 wherein the signal analyzer determines an output signal indicative of a state of processing of the wafer, a condition of the process chamber, or a state of a plasma in the process chamber.

88. An apparatus according to claim 81 wherein one or more of the non-optical parameters comprise a temperature, a chamber pressure, a foreline pressure, a presence of a reactive gas, an RF parameter, or a system controller parameter.