| 摘要 |
PROBLEM TO BE SOLVED: To provide a device for measuring a difference in the thickness of a liquid membrane which enables measurement of the thickness of the liquid membrane of several microns or less. SOLUTION: The device for measuring the liquid membrane thickness measures the thickness of the liquid membrane on a substrate after the substrate is treated with a treatment liquid while it is rotated. The device includes an imaging camera 7 which detects a variation in the color gradation of an interference fringe generated by the treatment liquid remaining on the substrate and a processing device 8 which calculates the thickness of the treatment liquid on the substrate from the variation in the color gradation detected by the imaging camera, using an expression (2ndcosθ=mλ) of optical diffraction. In the expression, n is a refractive index of the treatment liquid, d the thickness of the liquid membrane,θan incidence angle of light on the treatment liquid, m an integer andλa wavelength of light. COPYRIGHT: (C)2010,JPO&INPIT
|
