Multi-Scale Measurement and Evaluation for Sub-Nanometer Size of Surface Profile

本研究旨在对亚纳米级尖端制造工艺所产生的超精加工表面的多尺度特性进行测量和评价，目的是根据HD基片和磁介质磁头的表面光洁度等级，从实验上明确表面频率-振幅关系从1/f到白色的特性变化，本研究通过对垂直扫描白色光干涉显微镜测量得到的真实的表面数据进行分形分析，明确了表面结构的变化规律，建立了超文件表面结构模型，并对超文件表面结构模型进行了验证从Ra值为亚纳米级的被测表面的功率谱密度分析。测量中对显微镜的视场进行了选择，获得了宽谱密度，结果表明，在亚纳米Ra的表面上，表面轮廓的功率谱密度的斜率随着Ra值的减小而减小。分形维数随Ra值的减小而增大。在最精细的表面上，尺寸达到2，这是一个不可能的值。这意味着这些表面将其属性从分形区域更改为接近白色区域。

This research aims at the measurement and evaluation of multi-scale properties of extremely finished surface which is produced by leading-edge manufacturing process in order of sub-nanometer.The purpose is to dear experimentally the property change of surface frequency-amplitude relation from 1/f to white in accordance with the grade of surface finish of HD substrate and head of magnetic media, and to contribute the fields of surface analysis and functional modeling of surface structure of above mentioned fine finished parts.This research made clear the change of surface structure by Fractal analysis from real surface data which was measured by vertical scanning white light interferometric microscope.Super file finished surface structure was analyzed from power spectrum density of measured surface which has sub-nanometer Ra value. The measurement has done selecting the field of view of microscope so that wide spectrum density was acquired.As the results, in the surface that has sub-nanometer Ra the slope of power spectral density of surface profile decreases with decrease its Ra value. Then the Fractal dimension increases with decrease Ra value. At the finest surface the dimension reached 2 which is a impossible value. This means these surfaces change its property from Fractal region to near white region.