| 摘要 |
PROBLEM TO BE SOLVED: To provide a film thickness measurement method and a film thickness measurement device allowing for accurate measurement of the thickness of a thin film on a top surface of a substrate even when the thin film is formed both on the top surface and the rear surface of the substrate.SOLUTION: A film thickness measurement device 1A includes: a light irradiation part 10 for irradiating a measurement object 100 with light; a light detection part 20A for detecting the intensity of reflected light for each wavelength thereof; and a film thickness calculation part 30a for determining a film thickness of a first film 102 by comparing the actually-measured spectral reflectance obtained based on the detection result in the light detection part 20A, surface reflectance, surface transmittance, and theoretical spectral reflectance with the rear surface reflectance taken into account, with each other. The film thickness calculation part 30A compares a plurality of theoretical spectral reflectances and actually-measured spectral reflectances which are obtained by changing each of a value of the surface reflectance, the value of surface transmittance, and the value of the rear surface reflectance, and determines the film thickness of the first film 102 based on the theoretical spectral reflectance closest to the actually-measured spectral reflectance. |
