MINIMIZING THE SIZE OF FORCE-CONTROLLED POINT CONTACTS ON SILICON FORCARRIER PROFILING

The spatial distribution of charge carriers in semiconducting conducti ve properties. In this report silicon cantilevers with integrated tips and coated with boron-doped chemical vapor deposited diamond have bee n used for the first time to establish electrically reliable point con tacts on silicon. The relation between the applied force and the nanoi ndentation characteristics has been investigated in a range from 10 to 150 mu N. The threshold value necessary to pierce the native oxide la yer has been obtained and is found to depend on the peculiar coating o f each tip. The data are correlated with the current-voltage character istics of the contacts. The impedance of point contacts on homogeneous ly doped p- and n-type silicon with known resistivity has been measure d and calibration curves have been plotted for nanospreading resistanc e probe measurements. It is found that only above the threshold for pl astic deformation can useful electrical characterizations be performed . (C) 1996 American Vacuum Society.