Top-contact Copper phthalocyanine (CuPc) thin-film field-effect transistor (TFT) with SiO2/Ta2O5/SiO2 (STS) multilayer as the dielectric was fabricated and investigated. With the multi-layer dielectric, drive voltage was remarkably reduced. A relatively large on-current of 1 1 x 10(-7) A at a VGS of -15 V was obtained due to the strong coupling capability provided by the STS multilayer gate insulator. The device shows a moderate performance saturation mobility of mu(sat) = 6.12 x 10(-4) cm(2)/V s, on-current to off-current ratio of I-on/I-off = 1 1 x 10(3), threshold voltage of V-TH = -32 V and sub-threshold swing SS = 1.6 V/dec Atomic force microscope images show that the STS multilayer has a relative smooth surface Experiment results indicate that STS multilayer is a promising Insulator for the low drive voltage CuPc-based TFTs. (C) 2010 Elsevier B V All rights reserved.