Charge-Transport Anisotropy Due to Grain Boundaries in Directionally Crystallized Thin Films of Regioregular Poly(3-hexylthiophene)

P3HT films that are highly anisotropic inplane are produced using a directional crystallization technique, and the charge-transport properties of grain boundaries between different orientations of crystallites are studied. Boundaries along the fiber provide a small barrier to charge transport when compared to fiber-to-fiber grain boundaries. The films allow a correlation to be drawn between the grain-boundary type and charge-tran sport behavior in P3HT