MEASURING SURFACE TOPOGRAPHY WITH SCANNING ELECTRON MICROSCOPY. II. Analysis of three estimators of surface roughness in second-dimension and third-dimension.

PONZ E; LADAGA JL; BONETTO, RD

MICROSCOPY & MICROANALYSIS

Cambridge University Press

Año: 2006 vol. 12 p. 170 - 177

1431-9276

The scanning electron microscope (SEM) is widely used in the surface studies and continuous efforts are carried out in  the search of estimators of different surface characteristics. By using the variogram , we  developed two of these estimators which were used to characterize the surface roughness  from the SEM image texture. One of them is related with the crossover between fractal region at low scale and the periodic region at high scale, while the other estimator characterizes the periodic region.  In this work a full study of these estimators and the fractal dimension in 2D and 3D dimensions was carried out for emery papers. We  show that the obtained fractal dimension  with only one image is good enough to characterize the roughness surface, because its behavior is similar to those obtained with 3D height data. We show also that the estimator which indicates the crossover is related  to the minimum cell size in 2D and to the average particle size in 3D. The other estimator  has different values for the three studied emery papers in 2D but it does not have a clear meaning and these values are similar for these studied samples in 3D;  nevertheless, it indicates the formation tendency of compound cells.  The fractal dimension values from the variogram and from an area vs. step log-log graph were  studied with 3D data. Both methods yield different values corresponding to different information from the sample.