The invention relates to the related technical field of
semiconductor wafers, in particular to a full-automatic
wafer film thickness detection method and
system based on spectral reflection, and the method comprises the steps: obtaining a
wafer surface reflection spectral
signal, and extracting spectral feature information and
wavelength parameters; identifying a polarization characteristic parameter and an interface interference characteristic parameter, introducing the
wavelength parameter as an adjusting variable, determining a
wavelength dependence term, and generating a global film thickness distribution map, thereby solving the problems that in a detection scene with a multi-layer film or a rough interface, the influence of an incident light polarization state on a reflection
signal is not fully considered, the reflection
signal characteristic extraction is distorted, and the detection accuracy is poor. According to the method, the technical problem that the film thickness obtained through reflection characteristic
backstepping deviates from the actual film thickness is solved, polarization characteristic parameters and interface interference characteristic parameters are recognized, the thickness of each detection point is determined after the film
refractive index is corrected, the thickness detection precision is effectively improved, and the influence of spectral signal
noise and interface interference is reduced; the technical effect of accurately presenting the global film thickness distribution of the
wafer film is achieved.