Poly(3-hexylthiophene):6,13-bis(triisopropylsilylethynyl)-pentacene (P3HT:TP) blends with a ratio of 1:1 (wt/wt) were deposited via spin coating on anodized oxide (Al2O3). A phase separation of the compounds was observed, resulting in the formation of crystalline aggregates of TP molecules that segregate vertically on the surface. The form of segregation depends on the oxide surface treatment used. Spectroscopy analysis shows a higher molecular order of P3HT in the blend than for neat film and that TP molecules are also distributed in the polymeric matrix. Regarding the OFET characteristics, charge carrier mobilities of 1.2 x 10(-3) cm(2) V-1 s(-1) and 2.0 x 10(-3) cm(2) V-1 s(-1) were obtained from devices for untreated and (hexamethyldisilazane) HMDS-treated Al2O3 gate dielectric, respectively. These results confirm that P3HT:TP blends have good potential as an active layer in organic field effect transistors (OFETs). (C) 2016 Elsevier B.V. All rights reserved.