High-K and High-Temperature-Resistant Polysilsesquioxane: Potential for Solution-Processed Metal Oxide Semiconductor Transistors Operating at Low Voltage

Abstract

Solution-based deposition has recently been proposed as a low-cost flexible electronics alternative. Therefore, the development of appropriate solution-processed materials for metal oxide semiconductor transistors has become more important. In recent years, high dielectric constant (k) polymer insulators have been developed that can withstand relatively high heat until the metal oxide structure is restructured and can be operated at low voltage with high performance. We produced ladder-like polysilsesquioxanes(LPSQ) with two functional epoxy and phenyl groups to increase k and heat resistance at once for solution-processed metal oxide semiconductors. Here, the LPSQ films showed a roughness value of 0.521 nm, high-k characteristics (>8) and good thermal resistance (>380°C). LPSQ films were used as a dielectric in a high-performance solution-processed indium oxide semiconductor, which in turn was used to fabricate n-type field-effect transistors (FETs). The 350°C-annealed indium oxide FETs with the LPSQ dielectric showed good FETs performance with mobility of 7.07 cm2/Vs.

Keywords: high-temperature process, metal oxide semiconductor, High dielectric constant, low-voltage operation, spray coating