Junctionless Coplanar-Gate Oxide-Based Thin-Film Transistors Gated by Al2O3 Proton Conducting Films on Paper Substrates
WU Guo-Dong1**, ZHANG Jin2, WAN Xiang1
1School of Electronic Science and Engineering, Nanjing University, Nanjing 210093 2Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201
Abstract：Nanogranular Al2O3 films deposited by plasma-enhanced chemical vapor deposition show a high proton conductivity of ～1.25 × 10?4 S/cm and a huge electric-double-layer (EDL) capacitance of ～4.8 μF/cm2 at room temperature. Using nanogranular Al2O3 proton conducting films as gate dielectrics, junctionless indium-zinc-oxide (IZO) thin-film transistors (TFTs) with a coplanar-gate configuration are fabricated. The unique feature of such junctionless TFTs is that the channel and source/drain electrodes are the same thin IZO film without any source/drain junction. Due to the strong EDL capacitive coupling triggered by mobile protons in nanogranular Al2O3, these TFTs show a low-voltage operation of 1.5 V and a high performance with a large field-effect mobility (>18 cm2/V?s), a small subthreshold swing (<130 mV/decade) and a high current on/off ratio (>106). Our results demonstrate that such junctionless TFTs gated by Al2O3 proton conducting films have great potential applications in low-power and low-cost electronics.
2014, Vol. 31 
