Control of field-induced switching at the surface of pentacene single crystals by organosilane self-assembled monolayers
Abstract
We examine a recently developed method to control field-effect of organic thin-film transistors by organosilane molecules in case of single-crystal devices. After source and drain electrodes are prepared on thermally oxidized doped Si substrates, highly ordered self-assembled monolayers (SAMs) of silanes with different electron affinities are formed on the silicon-oxide gate insulator. Then independently grown pentacen single crystals are attached by natural electrostatic force. Without gate voltage, the crystals on electron-affinitive F-terminated SAMs are more than five times more conductive than those on neutral Methyl-terminated SAMs. Sweeping the gate voltage, switch-on voltages differs typically by ∼ 20 V between the two types of the samples. In addition to similar results on polycrystalline thin-film transistors, it is convinced using the single-crystal devices that the electron affinitive SAMs act directly on the surface of the crystals to reduce interface trap levels, not (only) on grain boundaries.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARN37005T