Patent ID: 7411684

Claim:
A system comprising: an apparatus for processing a semiconductor wafer which performs a predetermined processing, as to a film on a surface of the semiconductor wafer to be processed disposed on a sample stand within a vacuum chamber, by using plasma generated within the vacuum chamber, the apparatus including: a light source which emits light having multiple wavelengths within the vacuum chamber; a port which is disposed so as to face on an inner surface of the vacuum chamber and through which light is transmitted from an inside of the vacuum chamber; a light receiving unit which receives, through the port, interference lights of multiple wavelengths reflected from the surface of the semiconductor wafer based on the light emitted from the light source during the processing of the semiconductor wafer; and a detecting device which detects a processed amount of the film during the processing of the semiconductor wafer based on a first pattern and a second pattern, wherein the first pattern is obtained by measuring intensities of the interference lights of multiple wavelengths received by the light receiving unit and obtaining a pattern of differential values of the measured interference light intensities using a wavelength as a parameter as the first pattern, and the second pattern is a pattern of differential values of intensities of interference lights of multiple wavelengths with respect to a predetermined processed amount of the film actually obtained in advance as to a sample semiconductor wafer having substantially same configuration as the semiconductor wafer a film thickness measuring apparatus for measuring a film thickness of a member to be processed, including: a differential waveform pattern data base for holding a standard pattern consisting of a time differential value of an interference light for each of multiple wavelengths with respect to a film thickness of a first member to be processed; a unit for measuring an intensity of an interference light for each of multiple wavelengths of a second member to be processed; a unit for obtaining a real pattern consisting of time differential values of measured interference light intensities; and a unit for determining a film thickness by using a pattern of zero-cross points of the differential values of intensities of the received interference light for a second wavelength among the received interference lights of the multiple wavelengths.