Russell Young and his co-workers Fredric Scire and John Ward (left to right) with the Topografiner.
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).
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).