Conductance and capacitance-frequency characteristics of polypyrrole/p-type silicon structures

We formed a polypyrrole/p-type silicon device by an anodization process. An aluminum electrode was used as an ohmic contact. From the current-voltage characteristics of the device, barrier height and ideality factor values of 0.662 eV and 1.734, respectively, were obtained from a forward-bias current-voltage plot. Low capacitance-frequency and conductance-frequency measurements from 0.00 to 0.30 V with steps of 0.02 V were made. At each frequency, the measured capacitance decreased with increasing frequency because of a continuous distribution of the interface states in the frequency range of 5.0 Hz to 2.0 MHz. (C) 2003 Wiley Periodicals, Inc.