Theoretical model of interface trap density using the spread of the differential capacitance characteristics in scanning capacitance microscopy measurements

In this letter, we propose a theoretical model for the calculation of interface trap density (D-it) in a metal-oxide-semiconductor structure using data from scanning capacitance microscopy (SCM) measurements. The model is based on the correlation of D-it with the change in the full width at half maximum of the SCM differential capacitance (dC/dV) characteristics. The good agreement between the calculated D-it values from the SCM theoretical model and the experimental midgap D-it values obtained from conductance measurements shows the validity of the proposed model. The model opens up possibilities for obtaining the spatial distribution (with nanometers resolution) of interfacial traps on a device using SCM measurements. (c) 2006 American Institute of Physics.