Numerical degradation method and system for reflectivity spectrum from rough surface to smooth surface and medium

• Main Authors: SHENG XINQING, GUO KUNYI, MOU YUAN, WU BIYI
• Format: Patent
• Language: Chinese; English
• Published: 03.09.2021
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

The invention belongs to the technical field of application of a rough surface reflectivity spectrum, and discloses a numerical degradation method and system for a reflectivity spectrum from a rough surface to a smooth surface and a medium. The reflectivity spectrum of a rough sample is measured, and a change curve of the surface roughness of the rough sample along with wavelength is inverted by combining a genetic algorithm; a quartic polynomial is adopted to carry out fitting on the roughness-wavelength curve; and the fitted roughness spectrum is substituted into a Kirchhoff expression of the Fresnel reflectivity of the rough surface, and the reflectivity spectrum of the smooth surface is solved. And a Lorentz function is adopted to carry out fitting correction on the solved smooth surface reflectivity spectrum, and the final result is matched with the reflectivity spectrum of the polishing sample. The method is suitable for a material of which the smooth surface reflectivity spectrum cannot be directly tes