Automatic optical device for roughness measurement based on differential scattering

摘要

The automatic measuring device for the control of technology and for polishing surface roughness measurements has been described in this work. This device has very high sensibility and allows to measure rms (root mean squared) roughness $sigma equal some angstroms. There is noncontactive and nondestructive photometric measurement. It is based on the differential scattering measurement. We develop the theoretical framework for the device to definite absolute quantity rms roughness $sigma and correlation length a. It has been demonstrated, that this device together with method allows to measure surface roughness of samples from different materials including transparent ones for laser light. It was foreseen that the scattering from the untest surface of sample would be let out. It allowed to measure the transparent samples without sputtering reflective film. Sensibility of definition of rms roughness is about 1 angstroms, with precision about 30%. The results of this measuring method were compared with ones obtained with other methods and it was received with good agreement. The results of the investigation of the surface samples roughness with different technology has been described. This method of measurement has an industrial application for controlling different surfaces roughness.