Electrical profiling of Si(001) p-n junctions by scanning tunneling microscopy

Potential distributions across Si(001)p-n junctions have been studied using cross-sectional scanning tunneling microscopy, spectroscopy, and potentiometry. A clear transition between p- and n-type material can be seen across each junction, and variations in the energy of the conduction-band edge can be detected with a spatial resolution of better than 100 Å. Current-voltage characteristics have been measured in both unbiased and electrically biased structures, and measurements under both conditions are consistent with calculated potential distributions.