×

Film thickness measurement device and film thickness measurement method

  • US 8,885,173 B2
  • Filed: 07/27/2010
  • Issued: 11/11/2014
  • Est. Priority Date: 10/13/2009
  • Status: Active Grant
First Claim
Patent Images

1. A film thickness measurement apparatus for measuring a temporal change in film thickness of a film-shaped measuring object having a first surface and a second surface, comprising:

  • a measurement light source supplying measurement light containing wavelength components over a predetermined band to the measuring object;

    detection means detecting intensities of output light, formed by superimposing reflected light of the measurement light from the first surface of the measuring object and reflected light of the measurement light from the second surface, at each time point by wavelength; and

    film thickness analysis means obtaining a temporal change in film thickness of the measuring object, whereinthe film thickness analysis means obtains a value corresponding to a peak wavelength where an intensity of interfering light generated by the reflected light from the first surface and the reflected light from the second surface interfering with each other is maximized or minimized or an interval of the adjacent peak wavelengths based on spectral waveforms of the output light respectively detected at two or more time points different from each other by the detection means, and obtains a temporal change in film thickness of the measuring object from a temporal change in the value corresponding to the peak wavelength or the interval of the adjacent peak wavelengths, and whereinthe film thickness analysis means calculates a difference I(T2)−

    I(T1) between a first spectral waveform I(T1) regarding the output light detected at a first time point T1 and a second spectral waveform I(T2) regarding the output light detected at a second time point T2 different from the first time point T1, and determines a zero-cross wavelength where the difference becomes zero as the peak wavelength.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×