Resistance Electric Field Dependence and Time Drift of Piezoresistive Single Crystalline Silicon Nanofilms

The piezoresistive properties of single-crystalline silicon nanofilms are studied. Resistors were fabricated on 130nm thick SOI-silicon and measurements indicate that the conductivity is extremely sensitive to substrate bias and can therefore be controlled by varying the backside potential. Another important parameter is the resistivity time drift. Long time measurements show a drastic variation in the resistance. Not even after several hours of measurement is steady state reached. The drift is explained by hole injection into the BOX as well as existence of mobile charges in the BOX. The piezoresistive effect was studied and shown to be the same as bulk silicon.