We report a solution-processed aluminum oxide (AlOx) film which is used as a gate dielectric for low-temperature polycrystalline silicon (LTPS) thin-film transistors (TFTs). After oxygen plasma treatment on the LTPS layer, AlOx layer could be uniformly coated on the poly-Si with a sol-gel method. The p-channel TFTs fabricated with an AlOx gate dielectric exhibited a field-effect mobility of 53.91 cm(2)/V s, threshold voltage of -1.7 V and gate voltage swing of 0.265 V/decade. A twenty-three stage ring oscillator made of the LTPS TFTs showed a switching speed of 1.32 MHz at a supply voltage of 15 V. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3594094] All rights reserved.