High-Performance Stretchable Organic Field-Effect Transistor Fabricated with an Ionic-Gel Dielectric

The intrinsically stretchable organic field-effect transistor (OFET) is an essential component of advanced stretchable electronics; however, the wide application of OFET devices still faces challenges of low stretchability and high power consumption. Here, the bilayer structure thermoplastic polyurethane (TPU)-[EMIM][BF₄]/TPU with high areal capacitance (1.27 μF cm^–2) was developed as a stretchable dielectric to fabricate a stretchable OFET with a low-operating voltage and a low-leakage current (<10^–6 A). Besides, the intrinsically stretchable active layer was fabricated by blending poly(3-hexylthiophene) with polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene to obtain an efficient high-performance OFET. The effects of an imidazolium-based ionic gel with different anion sizes on dielectric layer properties were studied; the as-developed OFET exhibited a high charge-carrier mobility μ of 5.19 cm² V^–1 s^–1 and an I_on/I_off of 10⁴. The stretchable OFET can withstand up to 50% biaxial stretching and maintain reliable electrical characteristics after stretching and release between 0 and 10% strain for 1000 cycles, and μ is 3.60 cm² V^–1 s^–1 and I_on/I_off is 2.40 × 10³ when it is stretched 10% along the channel length direction. At last, we manufactured the OFET for photoelectric detection and demonstrated its imaging application.