Veeco Dektak 150, User Manual

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E-14 3D Mapping Function
appears in the upper right corner of the Terms Removal dialog box. Select this box to set the
zero height to the mean of the current data. Otherwise, it is set to the height of parent.
Filtering Options
The filtering options create a modified data array to produce one of the effects described after the
figure.
Figure E-12: Processed Options Dialog Box - Filtering Tab
Low Pass Smoothing (Box Car Filter)
This filter removes the effects of high spatial frequency roughness, smoothing over features
that are smaller than the specified window size. The system eliminates small-scale
roughness, making the most significant features of the dataset become easier to distinguish.
Median Smoothing (Median Filter)
The median of the valid points in each window is used as the data element in the new,
smoother array. (In other words, it filters out noisy and "spiked" data.) The median is the
value of the middle point when the points are sorted from smallest to largest.
High Pass Smoothing (Edge Enhancing Filter)
High spatial frequencies are emphasized. This filter removes major undulations and large-
scale waviness, making small-scale roughness easier to distinguish.
Digital Filters (Fourier Filtering)
Digital filters selectively suppress roughness or waviness in a dataset. These filters work in
the spatial frequency spectrum of the dataset rather than on the pixels themselves. By
selecting different digital filter types, some of frequency content of the dataset can be
selectively removed from the image, accentuating or attenuating features of selected size
range. Select from the following digital filter options.