PRINCIPLE OF THE TOPOGRAFINER
The left (y) and right (x) piezo drivers scan the tip over and slightly above the specimen surface. The center (z) piezo is controlled by a servo system to maintain a constant voltage, and hence a constant vertical separation between the tip and the surface. An electron multiplier detects the tiny fraction of the tunneling current which is scattered by the specimen surface. The results of a scan are shown at the lower right.

Reference: R.D. Young, Physics Today 24, 42 (Nov. 1971).

FIRST SCANNING PROBE IMAGE
Topographic map of a 180-line-per-mm diffraction-grating replica, obtained with the Topografiner, a noncontacting field-emission probe developed at NBS.

Reference: R. Young, J. Ward, and F. Scire, Rev. Sci. Instrum. 43, 999 (1972).
 
 
 

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