| 摘要 |
PURPOSE:To enable the inspection of the surface at the same slice level as well as with the same sensitivity regardless of difference in material of a substrate, the type of a thin film and the thickness of a thin film, by correcting the sensitivity of a detection means for detecting scattered light according to the reference of the substrate. CONSTITUTION:Particles with the standard size of 2mum are adhered to a substrate and when the relationship between the reflectance and the output voltage thereof is plotted, the reflectance from the standard particles increases linearly with regard to the output voltage. The output voltage by the standard particles of the same size and the voltage applied to a photo electric multipler 6 also hold a linear relationship. The relationship between the relative reflectance and the applied voltage to the photoelectric multiplier can be obtained from these two relationships. Thus, the voltage to be applied to the photoelectric multiplier 6 is determined by finding the relative reflectance with respect to a silicon wafer. The output voltage will be equal to the output of a silicon wafer substrate by adjusting the voltage applied to the photoelectric multiplier 6 by a correction means 8 thereby enabling the discrimination of the size of the particles. |
