Solution-processed amorphous gallium-tin oxide thin film for low-voltage, high-performance transistors

Abstract

Gallium-tin oxide (GTO) semiconductor thin films were prepared by spin-coating with 2-methoxyethanol as the solvent. Their crystal structures, optical transparency, chemical states and surface morphologies, along with the electrical properties, were dependent on Ga contents and annealing temperatures. The optimized GTO channel layer was applied in the high-k Al 2 O 3 thin film transistor (TFT) with a low operation voltage of 2 V, a maximum field-effect mobility of 69 cm 2 V −1 s −1 , a subthreshold swing (SS) of 76 mV dec −1 , a threshold voltage of 0.67 V and an on-off current ratio of 1.8×10 7. The solution-processed amorphous-GTO-TFTs would promote the development of low-consumption, low-cost and high performance In-free TFT devices.

Design of SnO2:Ni,Ir Nanoparticulate Photoelectrodes for Efficient Photoelectrochemical Water Splitting

“…According to Salameh et al [ 23 ], the E g of SnO 2 decreased from 3.97 to 3.53 eV after Zn loading but increased to 4.45 eV after co-doping with F. Han et al were also able to reduce the energy gap of sol-gel-prepared SnO 2 films from 3.8 to 3.1 eV by using Ti alloying and the oxygen vacancies created [ 32 ]. In contrast to our results, Ren et al [ 8 ] found that the E g of SnO 2 was 3.87 eV and was not changed even after doping with 10–50% Ga. Additionally, Ni doping was found to increase the E g of the spray-deposited SnO 2 films from 4.03 to 4.09 eV [ 17 ]. Guo et al obtained SnO 2 electrode with an energy gap of 1.74 V after (Ni, S)-co-doping [ 33 ].…”

“…created [32]. In contrast to our results, Ren et al [8] found that the Eg of SnO2 was 3.87 eV and was not changed even after doping with 10-50% Ga. Additionally, Ni doping was found to increase the Eg of the spray-deposited SnO2 films from 4.03 to 4.09 eV [17]. Guo et al obtained SnO2 electrode with an energy gap of 1.74 V after (Ni, S)-co-doping [33].…”

“…In that paper, Benkara et al illustrated that the R rms strongly depends on the preparation and dipping conditions as well as the different kinetics of Fe and Ni needed for the growth of SnO 2 nanoparticles. It is well-known that low R rms reduces the carrier scattering inside the films, ensuring the high performance of TFTs [ 8 ]. Additional morphological investigation was carried out by taking cross-sectional images for the films, as shown in Figure S1 (Supplementary Materials) .…”

“…This oxide’s characteristics make it ideal for optoelectronics, solar cells, gas sensors, catalysis, and thin-film transistors (TFTs). Sn 4+ (4d 10 5s 0 ) is suggested to replace In 3+ in thin-film transistors to avoid the high cost of device fabrication [ 8 ]. On the other hand, and despite these many advantages of SnO 2 , its wide E g and low surface area limit its use in industrial applications such as hydrogen generation.…”

Widely tunable optical properties via oxygen manipulation in an amorphous alloy

“…Unlike crystals with periodic lattice structures, amorphous thin films possess long-range disordered structures [1][2][3][4]. They are very useful in various fields including optics, electronics and catalysis due to their fruitful kinds ranging from metals to insulators [5][6][7][8][9][10][11]. Nevertheless, it is difficult to widely tune their properties via the amorphous structural manipulation [12][13][14][15][16].…”