Au-Induced Directional Growth of Inkjet-Printed 6,13-Bis(triisopropylsilylethynyl) Pentacene

An inkjet printing method for directional crystallization was proposed that employs difference in surface energy to induce film growth with higher crystallinity and orderliness. Inkjet printing of 6,13-bis(triisopropyl- silylethynyl) pentacene, a small-molecule semiconductor was performed as a single-line film with the starting point set on a patch of Au film, which had been surface-treated to have a slightly higher dispersive surface energy than the dielectric substrate. A larger dispersive surface energy on the metal resulted in advanced contact-line pinning thereof between the liquid and the substrate and induced film growth along the printing direction. With the influence of the differential surface energy, larger grain size as well as more convergent crystalline microstructure was obtained, which is beneficial to the fabrication of organic thin-film transistors with improved electrical performance and device-to-device uniformity.