Tetracene Single Crystal Heterostructured with a Distyrylbenzene Crystalline Layer to Enhance Field-Effect Mobility

Abstract

The performance of organic single-crystal-based field-effect transistors is commonly influenced by interface defects derived from the dielectric layer and crystal surfaces. In this study, a tetracene (Tc) single crystal heterostructured with a distyrylbenzene (DSB) crystalline layer (DSB/Tc) was successfully prepared by the physical vapor transport method. By using a lower HOMO level and higher LUMO level of DSB than those of Tc to keep the charge transport channel away from the dielectric layer surface, the charge carriers are effectively evitable to be trapped by interface defects. The hole and electron mobilities of the DSB/Tc crystal extracted from field-effect transistors could be up to 1.20 and 0.07 cm²/(V·s), which has around 2.0- and 9.7-times enhancement compared with the Tc single crystal, respectively. Our primary results demonstrate that the heterostructured construction of a crystalline layer with an energy level blocking effect on an organic single crystal can remarkably enhance the field-effect mobility, which sheds brilliant light on the development of high-performance optoelectronic organic crystals for application in organic field-effect transistors.