Regulated Dewetting For Patterning Organic Single Crystals With Pure Crystallographic Orientation Toward High Performance Field-Effect Transistors

Fabrication of high-quality organic single-crystalline semiconductors and their deterministic patterning are core opportunities as well as challenges for large-scale integration of functional devices with high efficiency and boosted performance. Previous approaches on solution patterning of organic semiconductors have achieved efficient and versatile control of the position, alignment, and size of organic structures. However, the poorly controllable dewetting dynamics of organic solution gives rise to low crystallinity and disordered crystallographic orientation of generated organic architectures that limit their device performance. Here, 1D organic single-crystal arrays with high crystallinity, strict crystallographic alignment, precise position, tunable, and homogeneous size are fabricated by exploiting an asymmetric-wettability topographical template. Periodically arranged micropillars with lyophobic sidewalls and lyophilic tops permit the generation of capillary bridges, which enable unidirectional dewetting of organic solution and ordered packing of molecules. The 1D arrays present pure (100) crystallographic orientation with pi-pi stacking of molecules in the optimal direction of carrier transport, leading to high carrier mobility of 8.7 cm(2) V-1 s(-1) in the field-effect transistor measurements. A facile pressure sensor based on the patterned belt arrays is fabricated, exhibiting high sensitivity and long-term stability.