Patent ID: 7057744
Filing Date: 2006-06-06
Classification: B24B,G01B,G01N

Abstract:
1. A method for measuring thickness of a thin film, the method comprising: irradiating white light onto an area of a surface of a sample having an optically transparent thin film thereon, during polishing; detecting reflected light from said area of said sample due to the irradiation with said white light; and determining the thickness of said optically transparent film on said area by using information from the spectral waveform of the reflected light thus detected; wherein, in said step of determining the film thickness, the film thickness is determined by using information from the spectral waveform of the reflected light from said area which is selected from said surface by using information from at least one of the spectral waveform, reflectivity of the surface of the sample, and a frequency spectrum in the spectral waveform, on the basis of a characteristic quantity of the spectral waveform of the reflected light from said sample by the irradiation of said white light.