Anisotropic mobility in large grain size solution processed organic semiconductor thin films

The hollow pen method for writing thin films of materials from solution is utilized to deposit films of 6,13-bis(tri-isopropylsilylethynyl) pentacene (TIPS pentacene) onto SiO2 surfaces with pre-patterned source/drain gold contacts. We demonstrate that large domains are obtained for TIPS pentacene films deposited from 0.5–4.0wt% solutions with toluene. Crystalline grains with (001) orientation are observed to grow with sizes that can exceed 1mm along the writing direction. A preferred azimuthal orientation is also selected by the process, resulting in anisotropic field effect transistor mobility in the films.