| AVS 54th International Symposium | |
| Surface Science | Thursday Sessions |
| Session SS-ThP |
| Session: | Surface Science Poster Session |
| Presenter: | B.B. Ohlson, Western Washington University |
| Authors: | B.B. Ohlson, Western Washington University F.S. Wilkinson, Western Washington University D.L. Patrick, Western Washington University |
| Correspondent: | Click to Email |
Organic semiconductor (OS) thin films have attracted widespread interest for their potential use in electronics, optics, information storage, photovoltaics and many other applications. Since properties such as charge transport are known to be anisotropic in most crystalline structures, having control of crystallite orientation should lead to improvements in the tunability of devices such as organic thin film transistors (OTFTs) and organic light emitting diodes (OLEDs). Furthermore, by creating films that are highly crystalline, with large grain size, and thus less potential for charge trapping at the grain boundaries, charge transport characteristics can be optimized. We present a new approach for growing OS thin films using thermotropic nematic liquid crystal (LC) solvents to deposit tetracene films with long-range uniaxial order. The LC solvent imprints its directionality onto the crystalline tetracene film as it grows, resulting in larger, highly oriented crystals. Films were deposited via atmospheric-pressure sublimation onto substrates coated by a LC layer oriented using mechanically rubbed polyvinyl alcohol (PVA). This poster will describe the effects of different processing conditions, such as LC layer thickness, substrate temperature and flux rate on film morphology and crystallinity.