Oligo-p-phenylevinylene organic thin-film transistors with chemically modified dielectric surfaces

In this article, we report on organic thin film transistors based on a modified oligo-p-phenylevinylene oligomer, 1,4-bis[4-(4-octylphenyl)styryl]-benzene (oligo-S) on chemically modified gate dielectrics. Previously, we have reported on oligo-S devices fabricated on unmodified SiO2 surfaces [T. C. Gorjanc, I. Lévesque, C. Py, and M. D’Iorio, Appl. Phys. Lett. (submitted)]. By using either hexamethyldisilazane (HMDS) or octadecyltrichlorosilane (OTS), both the hole mobility and on/off current ratios, Ion/off, have been increased. Maximum mobilities and on/off ratios of 0.14 cm2/V s with Ion/off>106 and 0.26 cm2/V s with Ion/off>107 were achieved with HMDS and OTS modified devices, respectively.