Physicochemically stable polymer-coupled oxide dielectrics for multipurpose organic electronic applications

A chemically coupled polymer layer is introduced onto inorganic oxide dielectrics from a dilute chlorosilane-terminated polystyrene (PS) solution. As a result of this surface modification, hydrophilic-oxide dielectrics gain hydrophobic, physicochemically stable properties. On such PS-coupled SiO ₂ or AlO_x dielectrics, various vacuum- and solution-processable organic semiconductors can develop highly ordered crystalline structures that provide higher field-effect mobilities (μ_FETs) than other surface-modified systems, and negligible hysteresis in organic field-effect transistors (OFETs). In particular, the use of PS-coupled AlO_x nanodielectrics enables a solution-processable triethylsilylethynyl anthradithiophene OFET to operate with μ_FET ∼ 1.26 cm² V^-1 s^-1 at a gate voltage below -1 V. In addition, a complementary metal-oxide semiconductor-like organic inverter with a high voltage gain of approximately 32 was successfully fabricated on a PS-coupled SiO₂ dielectric. Ultrathin polymer layers were chemically coupled on oxide dielectrics with chlorosilane-terminated polystyrene (PS). The PS-brush layer was physicochemically stable and provided a smooth, hydrophobic surface to induce highly ordered crystalline structures of vacuum- and solution-processable organic semiconductors. In particular, PS-coupled AlO_x nanodielectrics allowed solution-processable organic field-effect transistors to operate at a gate voltage of approximately -1 V, with a field-effect mobility of ∼1.26 cm² V^-1 s ^-1.