Charge-Transport Anisotropy in a Uniaxially Aligned Diketopyrrolopyrrole-Based Copolymer.

Aligned films of a semiconducting DPP-based copolymer exhibit highly anisotropic charge transport with a band-like temperature dependence along the alignment direction and hole mobilities of up to 6.7 cm(2) V(-1) s(-1) . X-ray diffraction measurements reveal an exceptional degree of in-plane alignment, high crystallinity, and a dominant face-on orientation of the polymer backbones. The surprising charge-transport properties are interpreted in a tie-chain model consistent with anisotropic activation energies.