Measuring apparatus and plasma processing apparatus

• US 9,070,725 B2
• Filed: 03/30/2012
• Issued: 06/30/2015
• Est. Priority Date: 03/30/2011
• Status: Active Grant

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Matsudo, Tatsuo, Kimura, Hidetoshi
• Primary Examiner(s): Baldwin, Gordon R
• Assistant Examiner(s): Bennett, Charlee
• Application Number:
  US13/435,656
• Publication Number:
  US 20120247669A1
• Time in Patent Office: 1,187 Days
• US Class Current: 1/1
• CPC Class Codes: G01K 11/00 Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
• CPC Class Codes: G01K 5/50 arranged for free expansion or contraction
• CPC Class Codes: H01J 37/32972 Spectral analysis
• CPC Class Codes: H01L 21/67248 Temperature monitoring

Abstract

Provided a measuring apparatus includes a wavelength dispersion device which dispersed light reflected by one surface of an examination target having a thickness D and light reflected by a rear surface of the examination target, as incident light, a detector in which a plurality of photodetection elements receiving light dispersed by the wavelength dispersion device and detecting a power of the received light in are provided in an array shape, and a piezoelectric device which is attached to the detector to convert an applied voltage into a mechanical power, wherein the detector detects the power of the received light when the detector is shifted by the mechanical power converted by the piezoelectric device as much as d/m, where d is a width of each of the photodetection elements in an array direction and m is an integer equal to or greater than 2.

Claims

1. A measuring apparatus comprising:

a wavelength dispersion device which receives and disperses light reflected by a front surface of an examination target having a thickness D and light reflected by a rear surface of the examination target;

a detector in which a plurality of photodetection elements receiving the light dispersed by the wavelength dispersion device and detecting a power of the received light in are provided in an array shape;

a piezoelectric device which converts an applied voltage into a mechanical power, and shifts the photodetection elements by the mechanical power; and

a measuring unit which is configured to

calculate the thickness of the examination target based on a frequency analysis of the light power detected by the photodetection elements in such a state that the photodetection elements are not shifted and the light power detected by the photodetection elements in such a state that the photodetection elements are shifted as much as d/m in an array direction, where d denotes a width of each of the photodetection elements in the array direction, and m denotes an integer equal to or greater than 2, and

measure a temperature of the examination target based on a previously set relationship between the temperature and the thickness of the examination target.

2. The measuring apparatus of claim 1, wherein the piezoelectric device is attached to an end portion of the plurality of photodetection elements provided in the array shape.

3. The measuring apparatus of claim 1, wherein the detector is a charged coupled device (CCD) array or a photodiode array.

4. The measuring apparatus of claim 1, wherein the measuring apparatus is a Czerny-Turner type spectroscope.

5. The measuring apparatus of claim 1, wherein the measuring unit is configured to measure the temperature of the examination target when a thickness of the examination target is less than a maximum value (X_max) represented by following equation,

6. A plasma processing apparatus comprising:

a chamber in which a plasma process is performed on a processing target;

a susceptor on which the processing target is placed in the chamber; and

a measuring apparatus which measures a temperature of the processing target placed on the susceptor,

wherein the measuring apparatus comprises;

a wavelength dispersion device which receives and disperses light reflected by a front surface of the processing target having a thickness D and light reflected by a rear surface of the processing target;

a detector in which a plurality of photodetection elements receiving the light dispersed by the wavelength dispersion device and detecting a power of the received light in are provided in an array shape;

a piezoelectric device which converts an applied voltage into a mechanical power, and shifts the photodetection elements by the mechanical power; and

a measuring unit which is configured to

calculate the thickness of the processing target based on a frequency analysis of the light power detected by the photodetection elements in such a state that the photodetection elements are not shifted and the light power detected by the photodetection elements in such a state that the photodetection elements are shifted as much as d/m in an array direction, where d denotes a width of each of the photodetection elements in the array direction, and m denotes an integer equal to or greater than 2, and

measure a temperature of the processing target based on a previously set relationship between the temperature and the thickness of the processing target.

7. A plasma processing apparatus comprising:

a chamber in which a plasma process is performed on a processing target;

a susceptor on which the processing target is placed in the chamber; and

a measuring apparatus which measures a temperature of a member of the plasma processing apparatus, a thickness of the member being larger than a thickness of the processing target,

wherein the measuring apparatus comprises;

a wavelength dispersion device which receives and disperses light reflected by a front surface of the member and light reflected by a rear surface of the member;

a detector in which a plurality of photodetection elements receiving the light dispersed by the wavelength dispersion device and detecting a power of the received light in are provided in an array shape;

a piezoelectric device which converts an applied voltage into a mechanical power, and shifts the photodetection elements by the mechanical power; and

a measuring unit which is configured to

calculate the thickness of the member based on a frequency analysis of the light power detected by the photodetection elements in such a state that the photodetection elements are not shifted and the light power detected by the photodetection elements in such a state that the photodetection elements are shifted as much as d/m in an array direction, where d denotes a width of each of the photodetection elements in the array direction, and m denotes an integer equal to or greater than 2, and

measure a temperature of the member based on a previously set relationship between the temperature and the thickness of the member.