Effects of P-Type SnOx Thin-Film Transistors with N2 and O2 Ambient Furnace Annealing

Recently oxide-based thin-film transistors (TFTs) are investigated for emerging applications of the next generation display devices and other electronic circuits (Fortunato, E., et al., 2012. Oxide semiconductor thin-film transistors: A review of recent advances. Advanced Materials, 24, pp.2945-2986). Despite of the great success in n-type oxide semiconductors with high transparency and high field-effect mobility, high performance p-type oxide TFTs are so highly desired that complementary circuits can be realized with low power and high performance (Ou, W.C., et al., 2008. Anomalous p-channel amorphous oxide transistors based on tin oxide and their complementary circuits. Applied Physics Letters, 92, p.122113). There are some oxides such as SnO, CuO, Cu2O and NiO are regarded as promising p-type semiconductor materials. In this investigation, tin oxide SnOx is fabricated to be active layer for TFTs device, and furnace annealing with several combinations of nitrogen and oxygen ambient is compared to enhance the electrical characteristics of p-type SnOx TFTs (Park, K.S., et al., 2009. High performance solution-processed and lithographically patterned zinc-tin oxide thin-film transistors with good operational stability. Electrochemical and Solid-State Lett., 12, pp.H256-H258). The results show that with N-2 + O-2 ambient, 30 minutes furnace annealing, the p-type SnOx TFTs device shows better performance with mobility (mu(FE)) 0.883 cm(2)/V.S, threshold voltage (V-T) -4.63 V, subthreshold swing (SS) 1.15 V/decade, and I-on/I-off ratio 1.01 x 10(3).