Patent ID: 7724872

Claim:
An inspection method for a thin film stack, comprising the steps of: placing a substrate, on which a stack formed by stacking a plurality of thin films is provided, on a sample board; applying an X-ray from a side surface of the stack in the direction crossing the thin film laminating direction; changing an incident angle (θ) of the X-ray to the side surface of the stack or wavelength of the incident X-ray to measure dependence on incident angle of reflectivity of the X-ray reflected from the stack or dependence on wavelength of the X-ray; wherein a shape of the X-ray beam incident to the stack is 10 μm or less in a short side or a short diameter at a position of the stack placed on the sample board; acquiring a curve indicating dependence on scattering vector of the X-ray reflectivity by converting the incident angle or the X-ray wavelength to a scattering vector; q=(4π/λ)sin θ; and obtaining film thickness of the stack with the minimum square analysis method of a measured reflectivity curve obtained from dependence on scattering vector of the X-ray reflectivity and a theoretical reflectivity curve derived theoretically.