Simultaneous control of molecular orientation and patterning of small-molecule organic semiconductors for organic transistors

Abstract

Triethylsilylethynyl anthradithiophene (TES-ADT) has been shown to be a promising soluble semiconductor for the active layer of organic field-effect transistors (OFETs) due to its solution processability, chemical stability and excellent electrical properties. However, there are still some problems that need to be resolved for the utilization of TES-ADT in OFETs. One of these problems is a patterning issue to minimize crosstalk between neighboring TES-ADT FETs. To this end, TES-ADT crystals of various shapes need to be patterned at the desired positions. Here, we demonstrated a simple method to fabricate patterned TES-ADT crystals by using a PDMS mold containing 1,2–dichloroethane (DCE) solvent. This method serves the dual purpose of preparing a variety of pattern shapes while simultaneously changing as-spun TES-ADT thin films into crystal patterns. The top-contact OFETs with the TES-ADT crystal patterns exhibited high performance, reaching a field-effect mobility of ∼0.3 cm2 V−1s−1.