Gogoi P.,Sibsagar College Assam |
Saikia R.,Sibsagar College Assam |
Saikia D.,Sibsagar College Assam |
Dutta R.P.,Sibsagar CollegeAssam |
Changmai S.,Sibsagar College Assam
Physica Status Solidi (A) Applications and Materials Science | Year: 2015
In this paper, the electrical properties of top-gated thin-film transistors with low-cost chemical bath deposition (CBD) of ZnO as active material and a high-k rare-earth oxide La2O3 as gate dielectric have been reported. The source-drain and gate electrodes and dielectric layers are fabricated by thermal evaporation techniques in high vacuum of the order of 10-6 Torr in a coplanar electrode structure. The channel length of the TFT is of 50 μm. The fabricated TFTs are annealed at 500 C in air. The TFTs exhibit a field effect mobility 0.58 (cm2 V-1 s-1). Use of a high dielectric constant (high-k) gate insulator reduces the threshold voltage and subthreshold swing of the TFTs. The TFTs exhibit a low threshold voltage of 4 V. The calculated values of gain-bandwidth product and subthreshold swing are also evaluated and presented. The ON/OFF ratio of the TFT is found to be 106. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.