ABSTRACTCurrent-voltage characteristics of organic semiconductor pentacene were studied as a function of applied tip force using conducting probe atomic force microscope. I-V measurements were performed on 150Å and 300Å pentacene films. No electrical contact was observed until 20 nN of tip force for the 150Å film coverage, whereas electrical contact was established easily with a few nN of tip force values for the 300Å film coverage. On both films, once an electrical contact was obtained, the conductance was observed to increase with increasing load. At about 50 nN and higher loads we lost electrical contact in both cases in a reproducible manner. While I-V on 150Å pentacene film showed a rectifying behavior, I-V on 300Å pentacene looked like typical I-V curves of tunneling phenomenon. From these measurements, we have estimated a hole injection barrier of about 0.76 eV and a band gap of about 2.00 eV for pentacene. These results are in agreement with those in the literature.
Current-Voltage Characteristics of the Metal / Organic Semiconductor / Metal Structures: Top and Bottom Contact Configuration Case
