@article {Jang:2012:1533-4880:1220,
	author = "Jang, Mi and Yang, Hoichang",
	title = "Structural Control Over Self-Assembled Crystals of -Conjugated Poly(3,3-didodecyl-quaterthiophene) for Organic Field-Effect Transistor Applications",
	journal = "Journal of Nanoscience and Nanotechnology",
	volume = "12",
	number = "2",
	year = "2012",
	abstract = "Liquid-crystalline (LC) poly(3,3&#8244;-didodecyl-quaterthiophene) (PQT-12) was investigated to optimize its side alkyl ordering and <I>&#960;</I>-conjugated structure for high performance organic field-effect transistor (OFET) applications. Initially, low-crystal films spun-cast on OTS-treated SiO<SUB>2</SUB> substrates were further crystallized via either thermal or solvent treatments. At temperatures (125-138 &#176;C) driving a LC state of PQT-12, mobile chains were better migrated into preformed crystals. The resulting films showed highly crystal nanofibrils, in which <I>&#960;</I>-conjugated polymer backbones (with an conjugated backbone spacing, <I>d</I><SUB>(010)</SUB> of 3.80 &#197;) and the orientation of self-assembled side-chains were tilted with respect to the film surface, respectively. However, via melting or solvent exposure providing isotropic states, film crystallization generated less ordered crystals with randomly oriented side-chains, increasing <I>d</I>(<SUB>010</SUB>) up to 4.16 &#197;. As a result, the usage of LC characteristic allowed us to consistently achieve the desirable crystal structure of PQT-12 and to robustly obtain high field-effect mobility for FET applications.",
	pages = "1220-1225",
	url = "http://www.ingentaconnect.com/content/asp/jnn/2012/00000012/00000002/art00062",
	doi = "doi:10.1166/jnn.2012.4578",
	keyword = "PQT-12, ORGANIC ELECTRONICS, ORIENTATION, CONJUGATION"
}