The effect of octadecyltrichlorosilane (OTS) treatment on the electronic properties of organic thin-film transistors is investigated using soft x-ray absorption and emission spectroscopy. Analysis of Carbon Kα x-ray emission spectra reveals that treating the SiO2 layer with OTS prior to pentacene deposition increases the number of π -bonding states in the active pentacene layer, which is strongly correlated with the conduction of charge carriers. The role of the increased π -bonding states is verified by measuring the current-voltage characteristics of pentacene thin-film transistors with and without OTS treatment. Drain current and field-effect mobility of OTS-treated samples are significantly enhanced as anticipated from the spectroscopic analysis.
Bibliographical noteFunding Information:
This work is supported by BK21 project of the Korea Research Foundation, the Yonsei Center for Nano Technology, grants from the Natural Science and Engineering Research Council of Canada (NSERC), and the Saskatchewan Synchrotron Institute.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)