Positioning growth of NPB crystalline nanowires on the PTCDA nanocrystal template

Hong Wang, Haiping Lin, Xing Fan, Stefan Ostendorp, Yandong Wang, Lizhen Huang, Lin Jiang, Youyong Li, Gerhard Wilde, Harald Fuchs, Wenchong Wang, Lifeng Chi

Abstract

Non-planar organic molecules often form amorphous films via vapor phase deposition on surfaces. In this study, we demonstrate for the first time that direct crystalline growth of non-planar NPB is possible when the orientation of initially deposited molecules on a PTCDA nanocrystal template is controlled to make it analogous to the structure of the molecular crystal. The crystalline NPB nanowires can be further positioned by controlling the site-selective growth of PTCDA nanocrystal templates at pre-determined locations. Short channel bottom contact OFET array with the NPB nanowires directly grown on electrodes were subsequently fabricated. The hole mobility of NPB nanowires is improved by 40-fold in comparison to that of the amorphous films.