Integrated film thickness measuring system and method used in integrated circuit manufacturing

The invention discloses an integrated film thickness measuring system and method for integrated circuit manufacturing, and the system comprises an incident light path which is used for focusing linearly polarized light at a to-be-measured point on the surface of a wafer, and a transmission light path which is used for obtaining a spectrum to calculate the ellipsometry parameter of the surface of a measured sample. The two refraction light paths are branched from the transmission light path and are used for obtaining an extra spectrum through refraction so as to calculate the ellipsometry parameter of the surface of the detected sample. According to the technical scheme, an unconventional optical system is adopted, after linear polarized light is reflected by a wafer, reflected light beams are collimated by a subsequent collimation system, are reflected and transmitted by a spectroscope, respectively enter different polarization verifiers, and then are focused on entrance slits of corresponding spectrometers b