Measuring apparatus and plasma processing apparatus

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.

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.