In this article, we reported the stacked structure zinc–indium-tin oxide (ZITO) thin-film transistors (TFTs) with graphene nanosheets (GNSs) prepared by solution process. GNSs were used as bridge ...layer between dual-ZITO layers. The transmission of stacked ZITO/GNSs/ZITO films are more than 80% in the visible region and the resistivity of ZITO films with GNSs bridge layer decreased from 502.9 to 13.4 Ω cm. The solution-processed TFT devices with GNSs bridge layer exhibited a desirable characteristic with a subthreshold slope of 0.25 V/dec and current on–off ratio of 1 × 107, and the saturation filed effect mobility is improved to 45.9 cm2V–1s–1, which exceeds the mobility values of the pristine ZITO TFTs by one order. These results demonstrate the solution-processed ZITO/GNSs/ZITO TFTs maybe make a further step to achieve high-performance TFTs and show the potential for next-generation applications.
•Transparent thin-film transistors (TFTs) were fabricated, characterized and modeled.•The thermal annealing of fabricated devices has enhanced their performances.•Thin-film transistors having the ...lowest Zn content showed the high performance.•The combined of annealing and low Zn content in the active layer result TFTs high performance.•The analytical model results are in close agreement with the experimental data.
In this study, we present a quantitative analysis of the electrical properties of a series of bottom- gate top-contact n-channel transparent thin film transistors (TFTs) based on zinc indium tin oxide (Zn-In-SnO) ternary compound with various ZnO content. In addition, the effect of annealing on the TFTs electrical properties was examined theoretically and experimentally. The obtained results revealed that the thermal annealing of fabricated devices in air atmosphere at 300 °C has enhanced their performances; this behavior is well observed for all devices fabricated with different composition of Zn-In-SnO. TFTs having the lowest Zn content of 17.1% and annealed 300°C showed the high electrical performances in term of drain current, saturation mobility, threshold voltage. For the total resistance modeling of the fabricated devices with various content of ZnO and that annealed 300 °C, grain boundary model based on Meyer–Neldel rule was applied. The obtained results revealed that the total resistance was increased with increasing ZnO content. Furthermore, an analytical model has been refined in order to reproduce the current-voltage relationships of the fabricated TFTs using the overall resistance obtained from the NMR–GBT model. The calculated results are in good agreement with the experimental measurements of all fabricated devices. The obtained performance of TFTs based on zinc indium tin oxide with low content of ZnO and annealed will be promising for application in the future backplane of flat panel displays.
It was demonstrated that low-operating-voltage bottom-gate top-contact (BGTC) structure thin-film transistors (TFTs) were fabricated using solution-processed amorphous zinc indium tin oxide (ZITO) ...and hafnium aluminum oxide (HAO) films. Due to the excellent chemical stability of ZITO film and high etching selectivity between ZITO and indium tin oxide (or between ZITO and Mo), the manufacture of BGTC structure requires only traditional lithography and wet etching. The usage of high-k HAO films lowered the operating voltage (below 2 V) of the TFT devices. TFT devices based on ZITO and HAO films annealing at 500 °C showed a saturated field-effect mobility of 13.5 cm 2 V -1 s -1 , a small subthreshold swing of 87 mV/decade, a large ON-to-OFF current ratio of 7.2 × 10 6 , and a threshold voltage of -0.6 V. The hysteresis (0.14 V) of TFT devices confirmed further that the ZITO and HAO films could be the promising candidates for TFT devices.
Measuring humidity in dynamic situation needs very high sensitive and fast response sensors. For this purpose, a new high sensitive humidity sensor based on ZnO/ITO (ZITO) composite nanostructure ...were designed on alumina substrate by sol–gel technique. Step by step monitoring of fabricated substrate after annealing at 400 °C was performed using scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and UV–Vis techniques. An oscilloscope and digital ohmmeter were applied to determine time-varying voltage and resistance signal of the fabricated sensors, respectively, while exposed to various humidity level. Sensitivity, response, recovery time, deposited layers thicknesses, composition ratio of ZnO:ITO and annealing temperature parameters were considered to achieve optimum conditions. The optimum conditions for maximum sensitivity were obtained as 1:1(ITO:ZnO) ratio, 400 °C annealing temperature, and three times layer by layer coating. Fabricated sensor has excellent response and recovery time (1.0 and 9 s) and long life time at room temperature (25 ± 1 °C) for monitoring human breath and dynamic situation.
This article examines and compares three very different interpretations of populism and Donald Trump’s 2016 presidential election: Ian Bremmer’s
Us vs. Them: The Failure of Globalism
; Jonah ...Goldberg’s
Suicide of the West
; and Salena Zito and Brad Todd’s
The Great Revolt
. Bremmer contends populism resulted in the U.S. and other nations when ruling elites failed to respond effectively to globalization’s rapidly rising inequalities. Goldberg sees deep-rooted divides in classical political philosophy (Rousseau v. Hobbes) as sources for contemporary identity politics on the sex-and-gender obsessed left and on the nativist/nationalist right. Based on direct interviews and supplementary survey data, Zito and Todd construct varying typologies of voter groups who supported Trump. None of the authors recognize that populism’s future may be seen in California where the effects of globalization, immigration and inequality are most pronounced.
The authors report the fabrication of a deep-ultraviolet sensitive a-ZITO thin-film-transistor (TFT) with a Ta 2 O 5 gate dielectric. It is found that carrier mobility, threshold voltage, and ...sub-threshold swing are 106.2 cm 2 /Vs, 0.75 V, and 0.45 V/decade, respectively, measured in the dark. It is also found that measured current increased from 2.3 × 10 -9 A to 7.97 × 10 -5 A, as we illuminated the sample with λ = 250-nm UV light when V G is biased at 0 V. Furthermore, it is found that deep-UV-to-visible rejection ratio could reach 2.3 × 10 5 for the fabricated Ta 2 O 5 /a-ZITO TFT.
Amorphous Zn–In–Sn–O (ZITO) films are grown by an rf magnetron cosputtering system from ceramic oxide targets of ZnO and ITO onto a flexible polyether sulfone (PES) substrate. The films exhibit ...resistivity as low as
1.22
×
1
0
−
3
Ω
cm
and optical transparency comparable to greater than that of Sn-doped indium oxide (ITO) films. The amorphous ZITO films have good mechanical durability compared to ITO films against the external dynamic stress measured by the bending tester. The deposited ZITO film has been used as a transparent anode in fabrication of the flexible organic light-emitting diode (OLED) by the cluster organic evaporator system. The amorphous ZITO anode-based flexible OLED shows comparable or superior current density and luminance characteristics compared to that of the amorphous ITO-based OLED.
► The quality of Zn–In–Sn–O (ZITO) films were adjusted by different gas (oxygen and argon) induced plasma ions bombarding (PIB) treatment. ► The contributions of PIB treatment on the structure, ...optoelectronic properties of ZITO film have been clearly defined. ► Briefly, PIB treatment can easily adjust the film quality in short time. ► Additionally, the film toughness not only was improved but also enhanced the structural stability by PIB treatment that was good for TCO film application in the flexible substrate.
The quality of co-sputtering derived Zn–In–Sn–O (ZITO) film was adjusted by different gas (oxygen and argon) induced plasma ions bombarding (PIB) treatment. The result showed that the film conductivity could be improved after plasma bombardment. The increment of oxygen vacancies and plasma bombard-induced thermal energy were main reasons. Notably, the efficiency of Ar plasma bombarded for improved conductivity not only was better but also had a smoother surface morphology. Due to Ar ions will not react with metal atoms to form oxide and possessed a higher momentum. In addition, the O-rich layer on the ultra-surface not only was removed but also enhanced film reliability by plasma bombarded that could enhance the performance of optoelectronic devices.
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