摘要
Depletion-mode indium zinc oxide channel thin film transistors (TFTs) with gate dimension of 1×200 μm and drain-to-source distance of 2.5 μm were fabricated on glass substrates using radio frequency magnetron sputtering deposition at room temperature. Plasma-enhanced chemical vapor deposited SiNx was used as the gate insulator. The threshold voltage was around -2.5 V. Saturation current density at zero gate bias voltage was 2 mA/mm, and a maximum transconductance of 7.5 mS/mm was obtained at Vds =3 V. The drain current on-to-off ratio was > 105. The maximum field effect mobility measured in the saturation region was ∼14.5 cm2 V-1 s-1. A unity current gain cutoff frequency, fT, and maximum frequency of oscillation, fmax of 180 and 155 MHz, respectively, were obtained. The equivalent device parameters were extracted by fitting the measured s parameters to obtain the intrinsic transconductance, drain resistance, drain-source resistance, transit time, and gate-drain and gate-source capacitance. © 2008 The Electrochemical Society.