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Poly(p-xylylene) derivatives, widely known as Parylenes, have been considerably adopted by the scientific community for several applications, ranging from simple passive coatings to active device components. Here, we explore the thermal, structural, and electrical properties of Parylene C, and further present a variety of electronic devices featuring this polymer: transistors, capacitors, and digital microfluidic (DMF) devices. We evaluate transistors produced with Parylene C as a dielectric, substrate, and encapsulation layer, either semitransparent or fully transparent. Such transistors exhibit steep transfer curves and subthreshold slopes of 0.26 V/dec, negligible gate leak currents, and fair mobilities. Furthermore, we characterize MIM (metal–insulator–metal) structures with Parylene C as a dielectric and demonstrate the functionality of the polymer deposited in single and double layers under temperature and AC signal stimuli, mimicking the DMF stimuli. Applying temperature generally leads to a decrease in the capacitance of the dielectric layer, whereas applying an AC signal leads to an increase in said capacitance for double-layered Parylene C only. By applying the two stimuli, the capacitance seems to suffer from a balanced influence of both the separated stimuli. Lastly, we demonstrate that DMF devices with double-layered Parylene C allow for faster droplet motion and enable long nucleic acid amplification reactions. [ABSTRACT FROM AUTHOR]

Although In2O3 nanofibers (NFs) are regarded as one of the active channel materials for next‐generation, low‐cost thin‐film transistors (TFTs), these NFs‐based devices still suffer from the degraded carrier mobility and operational instability, limiting the ability of such devices to replace current polycrystalline silicon technologies. Here, it is shown that nanofiber channel transistors with high electron mobility and operational stability can be achieved by selectively doping Zn element into electrospun In2O3 NFs. By precisely manipulating the doping level during NFs fabrication, their crystallinity, surface morphology, and corresponding device performance can be regulated reliably for enhanced transistor performances. It has been detected that InZnO/SiO2 TFTs with an optimized Zn doping concentration of 50% have demonstrated the high field‐effect mobility (µFE) of 6.38 cm2 V−1 s−1, the larger ION/IOFF of 4.12 × 107 and operation in the energy‐efficient enhancement‐mode. Low frequency noise (LFN) measurements have displayed that the scattering and defects inside the NFs are effectively suppressed by the particular microstructure. When integrating ALD‐derived Al2O3 films as the gate dielectric into TFTs devices, their electron mobility and ION/IOFF can be further improved to 37.82 cm2 V−1 s−1 and 2.92 × 108, respectively. To demonstrate the potential toward more complex logic applications, a low voltage resistor‐loaded unipolar inverter is built by using InZnO/Al2O3 TFT, exhibiting a high gain of 20.95 and full swing characteristics. These optimized parameters have demonstrated the significant advance of this electrospinning technique toward practical applications for high performance and large‐scale electronics. [ABSTRACT FROM AUTHOR]

Amorphous indium‐gallium‐zinc‐oxide (a‐IGZO) based memristive devices with molybdenum contacts as both top and bottom electrodes are presented aiming to be used in neuromorphic applications. Devices down to 4 µm2 are fabricated using conventional photolithography processes, with an extraordinary yield of 100%. X‐ray photoelectron spectroscopy and transmission electron microscopy performed on the developed structures confirm the presence of a thin intermixed oxide layer (4–5 nm) containing Mo6+ oxidation state at the interface with the bottom contact. This results in Schottky diode‐like characteristics at the pristine state with a rectification ratio of 3 orders of magnitude. The devices have electroforming‐free and area‐dependent analog resistive switching properties. Temperature analysis of resistive switching I–V data reveals barrier height variations of the junction. Several synaptic functions, such as synaptic potentiation and depression as response to programmed pulses, short‐ to long‐term plasticity transition (STP to LTP) and "learning experience" properties are presented. The Mo/IGZO/Mo memristive device shows potential application of an electronic synapse for brain‐inspired computing application. Integration in System‐on‐Panel architectures is possible at negligible cost, because all materials are used in commercial IGZO thin‐film transistor fabrication. [ABSTRACT FROM AUTHOR]

Solution combustion synthesis (SCS) has been widely used to produce simple and complex oxides with a desired morphology (size and shape). SCS is valuable due to low cost, simplicity and energy efficient synthesis. To guarantee the best molecular‐level mixing of reactants in an aqueous or solvent‐based solution some parameters need to be controlled, such as fuel type, metal cations precursors, stoichiometry ratio (φ), pH effect, atmosphere and initiation type. These determine the final properties of the oxide materials, providing the potential to reach different morphologies, which are essential for their final applications. This Review article focuses on the crucial parameters in SCS and how these affect the overall materials properties from nanostructures to thin films. To finalize, special attention is given to the application of SCS to form metal oxide thin films at low temperature and their application in thin film transistors (TFTs). [ABSTRACT FROM AUTHOR]

Lately, printed oxide electronics have advanced in the performance and low‐temperature solution processability that are required for the dawn of low‐cost flexible applications. However, some of the remaining limitations need to be surpassed without compromising the device electronic performance and operational stability. The printing of a highly stable ultra‐thin high‐κ aluminum‐oxide dielectric with a high‐throughput (50 m min−1) flexographic printing is accomplished while simultaneously demonstrating low‐temperature processing (≤200 °C). Thermal annealing is combined with low‐wavelength far‐ultraviolet exposure and the electrical, chemical, and morphological properties of the printed dielectric films are studied. The high‐κ dielectric exhibits a very low leakage‐current density (10−10 A cm−2) at 1 MV cm−1, a breakdown field higher than 1.75 MV cm−1, and a dielectric constant of 8.2 (at 1 Hz frequency). Printed indium oxide transistors are fabricated using the optimized dielectric and they achieve a mobility up to 2.83 ± 0.59 cm2 V−1 s−1, a subthreshold slope <80 mV dec−1, and a current ON/OFF ratio >106. The flexible devices reveal enhanced operational stability with a negligible shift in the electrical parameters after ageing, bias, and bending stresses. The present work lifts printed oxide thin film transistors a step closer to the flexible applications of future electronics. [ABSTRACT FROM AUTHOR]

A nonvacuum and low temperature process for passivating transparent metal oxides based thin-film transistors is presented. This process uses the epoxy-based SU-8 resist which prevents device degradation against environmental conditions, vacuum or sputtering surface damage. The incorporation of SU-8 as a passivation layer is based on the ability of this polymer to provide features with high mechanical and chemical stability. With this approach, lithography is performed to pattern the resist over the active area of the device in order to form the passivation layer. The resulting transistors demonstrate very good electrical characteristics, such as μFE=61 cm2/V s, VON=-3 V, ON/OFF=4.4×109, and S=0.28 V/dec. Electrical behavior due to the SU-8/metal oxide interface characteristics is also reported on the basis of Fourier transform infrared analysis. In contrast, we demonstrate how sputtering of SiO2 as a passivation layer results in severely degraded devices that cannot be switched-off. In order to obtain proper working devices, it is shown that SU-8 should be hard baked at 200 °C for 1 h in order to obtain a highly cross-linked polymer network. The stability of SU-8 passivated devices over the time of storage, under current bias stress and vacuum conditions is also demonstrated. [ABSTRACT FROM AUTHOR]

Recently, p-type metal–oxide–semiconductors have attracted considerable interests for the applications in optoelectronic devices and low-power complementary metal–oxide–semiconductor circuits. In this report, ternary p-type CuAlxOy semiconductor thin films were fabricated by sol–gel method and integrated as channel layers in thin-film transistors (TFTs). The electrical performances of CuAlxOy TFTs, together with the characteristics of CuAlxOy thin films (e.g., crystalline phases, chemical compositions, surface morphology, and optical transmittances), were systematically studied at various annealing temperatures (${T}_{a}$). The phase-pure CuAlO2 thin films were obtained at ${T}_{a}$ above 800° C in N2 atmosphere. CuAlO2 TFTs annealed at 900 ° C based on high-k Al2O3 exhibited optimized electrical performance, including a hole mobility of 1.36 cm2/Vs and on/off current ratio of $\sim 1 \times 10^{\textsf {5}}$. This paper not only demonstrates the successful fabrication of high-quality p-type CuAlO2 semiconductor thin film and electronic devices by sol–gel process but also provides guidelines for related ternary p-type oxide semiconductor material and device performance improvements. [ABSTRACT FROM AUTHOR]

Abstract: In this context, a simple, nontoxic, and eco‐friendly fully water‐induced (WI) route to fabricate ternary ZrGdOx thin films at various annealing temperatures is reported. Annealing temperature dependent microstructure, morphology, optical, electrical properties, and chemical bonding states of the WI ZrGdOx thin films are investigated by x‐ray diffraction, atomic force microscopy, optical spectroscopy, x‐ray photoelectron spectroscopy, and electrical measurements. A low leakage current density of 10−8 A cm−2 at 1 mV cm−1 and a large areal capacitance of 531 nF cm−2 at 20 Hz are observed for 400 °C‐annealed ZrGdOx thin films. To verify the possible applications of ZrGdOx thin films as the gate dielectric in thin‐film transistors (TFTs), WI In2O3/ZrGdOx TFTs are integrated. 250 °C‐derived full oxide In2O3/ZrGdOx TFTs have demonstrated high electrical performance and low operating voltage, including high µFE of 18.82 cm2 V−1 S−1, threshold voltage shift of 0.46 V under positive bias stress for 3600 s, and a large Ion/Ioff of 6.01 × 107, respectively. Finally, a low voltage resistor‐loaded unipolar inverter is built using In2O3/ZrGdOx TFT, exhibiting a linear relationship between supplied voltage and gain voltage and a maximum gain of 7.4 at 2.5 V. These optimized parameters have achieved a low operating voltage of 2 V, which represents a great step toward the achievement of low‐cost, low‐power consumption, and large‐area all‐oxide flexible electronics. [ABSTRACT FROM AUTHOR]

Solution-processed metal-oxide thin films with high dielectric constants (k) have been extensively studied for low-cost and high-performance thin-film transistors (TFTs). In this report, MgO dielectric films were fabricated using the spin-coating method. The MgO dielectric films annealed at various temperatures (300, 400, 500, and 600 °C) were characterized by using thermogravimetric analysis, optical spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and atomicforce microscopy. The electrical measurements indicate that the insulating properties of MgO thin films are improved with an increase in annealing temperature. In order to clarify the potential application of MgO thin films as gate dielectrics in TFTs, solution-derived In2O3 channel layers were separately fabricated on various MgO dielectric layers. The optimized In2O3/MgO TFT exhibited an electron mobility of 5.48 cm2/V s, an on/off current ratio of 107, and a subthreshold swing of 0.33 V/dec at a low operation voltage of 6V. This work represents a great step toward the development of portable and low-power consumption electronics. [ABSTRACT FROM AUTHOR]

High‐k alkaline lithium oxide (LiOx) thin films are fabricated by spin‐coating method. The LiOx thin films are annealed at different temperatures and characterized by various techniques. An optimized LiOx dielectric is achieved at an annealing temperature of 300 °C and exhibits wide bandgap of ≈5.5 eV, smooth surface, relatively permittivity of ≈6.7, and low leakage current density. The as‐fabricated LiOx thin films are integrated, as gate dielectrics, in both n‐channel indium oxide (In2O3) and p‐channel cupric oxide (CuO) transistors. The optimized In2O3/LiOx thin‐film transistor (TFT) exhibits high performance and high stability, such as Ion/Ioff of 107, electron mobility of 5.69 cm2 V−1 s−1, subthreshold swing of 70 mV dec−1, negligible hysteresis, and threshold voltage shift of 0.1 V under bias stress for 1.5 h. Meanwhile, the p‐channel CuO TFT based on LiOx dielectric shows high Ion/Ioff of 105 and hole mobility of 1.72 cm2 V−1 s−1. All the electrical performances are achieved at an ultra‐low operating voltage of 2 V. Considering the simple procedure, the moderate annealing temperature, and the low power consumption merits, these outstanding characteristics represent a significant advance toward the development of battery compatible and portable electronics. [ABSTRACT FROM AUTHOR]

Oxide semiconductor thin-film transistors can show anomalous behavior under bias stress. Two types of anomalies are discussed in this paper. The first is the shift in threshold voltage (VTH) in a direction opposite to the applied bias stress, and highly dependent on gate dielectric material. We attribute this to charge trapping/detrapping and charge migration within the gate dielectric. We emphasize the fundamental difference between trapping/detrapping events occurring at the semiconductor/dielectric interface and those occurring at gate/dielectric interface, and show that charge migration is essential to explain the first anomaly. We model charge migration in terms of the non-instantaneous polarization density. The second type of anomaly is negative VTH shift under high positive bias stress, with logarithmic evolution in time. This can be argued as electron-donating reactions involving H2O molecules or derived species, with a reaction rate exponentially accelerated by positive gate bias and exponentially decreased by the number of reactions already occurred. [ABSTRACT FROM AUTHOR]

Solution-processed p-type oxide semiconductors have recently attracted increasing interests for the applications in low-cost optoelectronic devices and low-power consumption complementary metaloxide-semiconductor circuits. In this work, p-type nickel oxide (NiOx) thin films were prepared using low-temperature solution process and integrated as the channel layer in thin-film transistors (TFTs). The electrical properties of NiOx TFTs, together with the characteristics of NiOx thin films, were systematically investigated as a function of annealing temperature. By introducing aqueous high-k aluminum oxide (Al2O3) gate dielectric, the electrical performance of NiOx TFT was improved significantly compared with those based on SiO2 dielectric. Particularly, the hole mobility was found to be 60 times enhancement, quantitatively from 0.07 to 4.4 cm²/V s, which is mainly beneficial from the high areal capacitance of the Al2O3 dielectric and high-quality NiOx/Al2O3 interface. This simple solution-based method for producing p-type oxide TFTs is promising for next-generation oxide-based electronic applications. [ABSTRACT FROM AUTHOR]

This paper presents a study concerning the role of channel length scaling on IGZO TFT technology benchmark parameters, which are fabricated at temperatures not exceeding 180\, ^\circC. The parameters under investigation are unity current-gain cutoff frequency, intrinsic voltage-gain, and on-resistance of the bottom-gate IGZO TFTs. As the channel length varies from 160 to 3 \mum, the measured cutoff frequency increases from 163 {\rm kHz} to 111.5 {\rm MHz}$, which is a superior value compared to the other competing low-temperature thin-film technologies, such as organic TFTs. On the other hand, for the same transistor dimensions, the measured intrinsic voltage-gain is changing from 165 to 5.3 and the on-resistance is decreasing from 1135.6 to 26.1 k$\Omega$ . TFTs with smaller channel length (3 $\mu$ m) have shown a highly negative turn-on voltage and hump in the subthreshold region, which can be attributed to short channel effects. The results obtained here, together with their interpretation based on device physics, provide crucial information for accurate IC design, enabling an adequate selection of device dimensions to maximize the performance of different circuit building blocks assuring the multifunctionality demanded by system-on-panel concepts. [ABSTRACT FROM PUBLISHER]

This paper presents a behavioral model for amorphous indium-gallium-zinc oxide thin-film transistor using artificial neural network (ANN) based equivalent circuit (EC) approach to predict static and dynamic behavior of the device. In addition, TFT parasitic capacitances (C and C) characterization through measurements is also reported. In the proposed model, an EC is derived from the device structure, in terms of electrical lumped elements. Each electrical element in the EC is modeled with an ANN. Then these ANNs are connected together as per the EC and implemented in Verilog-A. The proposed model performance is validated by comparing the circuit simulation results with the measured response of a simple common-source amplifier, which has shown 12.2 dB gain, 50 μW power consumption and 85 kHz 3-dB frequency with a power supply of 6 V. The same circuit is tested as an inverter and its response is also presented up to 50 kHz, from both simulations and measurements. These results show that the model is capable of capturing both small and large signal behavior of the device to good accuracy, even including the harmonic distortion of the signal (that emphasizes the nonlinear behavior of the parasitic capacitance), making the model suitable for IC design. [ABSTRACT FROM AUTHOR]

Solution-processed metal-oxide thin films based on high dielectric constant (k) materials have been extensively studied for use in low-cost and high-performance thin-film transistors (TFTs). Here, scandium oxide (ScOx) is fabricated as a TFT dielectric with excellent electrical properties using a novel water-inducement method. The thin films are annealed at various temperatures and characterized by using X-ray diffraction, atomic-force microscopy, X-ray photoelectron spectroscopy, optical spectroscopy, and a series of electrical measurements. The optimized ScOxthin film exhibits a low-leakage current density of 0.2 nA cm−2 at 2 MV cm−1, a large areal capacitance of 460 nF cm−2 at 20 Hz and a permittivity of 12.1. To verify the possible applications of ScOx thin films as the gate dielectric in complementary metal oxide semiconductor (CMOS) electronics, they were integrated in both n-type InZnO (IZO) and p-type CuO TFTs for testing. The water-induced full oxide IZO/ScOx TFTs exhibit an excellent performance, including a high electron mobility of 27.7 cm2 V−1 s−1, a large current ratio (IonIoff) of 2.7 × 107 and high stability. Moreover, as far as we know it is the first time that solution-processed p-type oxide TFTs based on a high-k dielectric are achieved. The as-fabricated p-type CuO/ScOx TFTs exhibit a large IonIoff of around 105 and a hole mobility of 0.8 cm2 V−1 at an operating voltage of 3 V. To the best of our knowledge, these electrical parameters are among the highest performances for solution-processed p-type TFTs, which represents a great step towards the achievement of low-cost, all-oxide, and low-power consumption CMOS logics. [ABSTRACT FROM AUTHOR]

In this study, we report solution-processed amorphous zinc tin oxide transistors exhibiting high operational stability under positive gate bias stress, translated by a recoverable threshold voltage shift of about 20% of total applied stress voltage. Under vacuum condition, the threshold voltage shift saturates showing that the gate-bias stress is limited by trap exhaustion or balance between trap filling and emptying mechanism. In ambient atmosphere, the threshold voltage shift no longer saturates, stability is degraded and the recovering process is impeded. We suggest that the trapping time during the stress and detrapping time in recovering are affected by oxygen adsorption/desorption processes. The time constants extracted from stretched exponential fitting curves are ≈106 s and 105 s in vacuum and air, respectively. [ABSTRACT FROM AUTHOR]

This paper presents analog building blocks that find potential applications in display panels. A buffer (source-follower), subtractor, adder, and high-gain amplifier, employing only n-type enhancement amorphous gallium–indium–zinc–oxide thin-film transistors (a-GIZO TFTs), were designed, simulated, fabricated, and characterized. Circuit simulations were carried out using a neural model developed in-house from the measured characteristics of the transistors. The adder–subtractor circuit presents a power consumption of 0.26 mW, and the amplifier presents a gain of 34 dB and a power consumption of 0.576 mW, with a load of 10 M\Omega//16 pF. To the authors’ knowledge, this is the highest gain reported so far for a single-stage amplifier with a-GIZO TFT technology. [ABSTRACT FROM PUBLISHER]

Here, a simple, nontoxic, and inexpensive 'water-inducement' technique for the fabrication of oxide thin films at low annealing temperatures is reported. For water-induced (WI) precursor solution, the solvent is composed of water without additional organic additives and catalysts. The thermogravimetric analysis indicates that the annealing temperature can be lowered by prolonging the annealing time. A systematic study is carried out to reveal the annealing condition dependence on the performance of the thin-film transistors (TFTs). The WI indium-zinc oxide (IZO) TFT integrated on SiO2 dielectric, annealed at 300 °C for 2 h, exhibits a saturation mobility of 3.35 cm2 V−1 s−1 and an on-to-off current ratio of ≈108. Interestingly, through prolonging the annealing time to 4 h, the electrical parameters of IZO TFTs annealed at 230 °C are comparable with the TFTs annealed at 300 °C. Finally, fully WI IZO TFT based on YO x dielectric is integrated and investigated. This TFT device can be regarded as 'green electronics' in a true sense, because no organic-related additives are used during the whole device fabrication process. The as-fabricated IZO/YO x TFT exhibits excellent electron transport characteristics with low operating voltage (≈1.5 V), small subthreshold swing voltage of 65 mV dec−1 and the mobility in excess of 25 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

This letter presents a novel high-gain four-quadrant analog multiplier using only n-type enhancement indium-gallium–zinc-oxide thin-film-transistors. The proposed circuit improves the gain by using an active load with positive feedback. A Gilbert cell with a diode-connected load is also presented for comparison purposes. Both circuits were fabricated on glass at low temperature (200 °C) and were successfully characterized at room temperature under normal ambient conditions, with a power supply of 15 V and 4-pF capacitive load. The novel circuit has shown a gain improvement of 7.2 dB over the Gilbert cell with the diode-connected load. Static linearity response, total harmonic distortion, frequency response, and power consumption are reported. This circuit is an important signal processing building block in large-area sensing and readout systems, specially if data communication is involved. [ABSTRACT FROM AUTHOR]

During the last years, oxide semiconductors have shown that they will have a key role in the future of electronics. In fact, several research groups have already presented working devices with remarkable electrical and optical properties based on these materials, mainly thin-film transistors (TFTs). Most of these TFTs use indium-tin oxide (ITO) as the material for source/drain electrodes. This paper focuses on the investigation of different materials to replace ITO in inverted-staggered TFTs based on gallium-indium-zinc oxide (GIZO) semiconductor. The analyzed electrode materials were indium-zinc oxide, Ti, Al, Mo, and Ti/Au, with each of these materials used in two different kinds of devices: one was annealed after GIZO channel deposition but prior to source/drain deposition, and the other was annealed at the end of device production. The results show an improvement on the electrical properties when the annealing is performed at the end (for instance, with Ti/Au electrodes, mobility rises from 19 to 25 cm²/V · s, and turn-on voltage drops from 4 to 2 V). Using time-of-flight secondary ion mass spectrometry (TOF-SIMS), we could confirm that some diffusion exists in the source/drain electrodes/semiconductor interface, which is in close agreement with the obtained electrical properties. In addition to TOF-SIMS results for relevant elements, electrical characterization is presented for each kind of device, including the extraction of source/ drain series resistances and TFT intrinsic parameters, such as μi (intrinsic mobility) and VTi (intrinsic threshold voltage). [ABSTRACT FROM AUTHOR]

The effects of zinc concentration on the performance of solution processed amorphous indium gallium zinc oxide (a-IGZO) thin film transistors (TFTs) have been investigated using high-k aluminum titanium oxide as gate dielectric. The x-ray diffraction results confirmed that all the IGZO channel layers are amorphous. The performance of a-IGZO TFTs were investigated in the linear regime operation. Highest linear field-effect mobility of 5.8 cm2/V s with an Ion/Ioff ratio of 6×107 and subthreshold swing of 0.28 V/dec were obtained for the a-IGZO (311) TFTs. The obtained performance of the a-IGZO TFTs is very promising for low-voltage display applications. [ABSTRACT FROM AUTHOR]

P-type thin-film transistors (TFTs) using room temperature sputtered SnOx (x<2) as a transparent oxide semiconductor have been produced. The SnOx films show p-type conduction presenting a polycrystalline structure composed with a mixture of tetragonal β-Sn and α-SnOx phases, after annealing at 200 °C. These films exhibit a hole carrier concentration in the range of ≈1016–1018 cm-3; electrical resistivity between 101–102 Ω cm; Hall mobility around 4.8 cm2/V s; optical band gap of 2.8 eV; and average transmittance ≈85% (400 to 2000 nm). The bottom gate p-type SnOx TFTs present a field-effect mobility above 1 cm2/V s and an ON/OFF modulation ratio of 103. [ABSTRACT FROM AUTHOR]

Keywords: fuel; metal oxides; nanostructures; solution combustion synthesis; thin film transistors EN fuel metal oxides nanostructures solution combustion synthesis thin film transistors 1 1 1 07/29/20 20200727 NES 200727 B Solution combustion synthesis b is a widely used low-cost, simple and energy-efficient approach to produce oxides with variable morphology. Fuel, metal oxides, nanostructures, solution combustion synthesis, thin film transistors. [Extracted from the article]

We report high-perfomance ZnO thin-film transistor (ZnO-TFT) fabricated by rf magnetron sputtering at room temperature with a bottom gate configuration. The ZnO-TFT operates in the enhancement mode with a threshold voltage of 19 V, a saturation mobility of 27 cm2/V s, a gate voltage swing of 1.39 V/decade and an on/off ratio of 3 × 105. The ZnO-TFT presents an average optical transmission (including the glass substrate) of 80% in the visible part of the spectrum. The combination o f transparency, high mobility, and room-temperature processing makes the ZnO-TFT a very promising low-cost optoelectronic device for the next generation of invisible and flexible electronics. [ABSTRACT FROM AUTHOR]

Solution-processed metal oxides have been investigated as an alternative to vacuum-based oxides to implement low-cost, high-performance electronic devices on flexible transparent substrates. However, their electrical properties need to be enhanced to apply at industrial scale. Amorphous indium-gallium-zinc oxide (a-IGZO) is the most-used transparent semiconductor metal oxide as an active channel layer in thin-film transistors (TFTs), due to its superior electrical properties. The present work evaluates the influence of composition, thickness and ageing on the electrical properties of solution a-IGZO TFTs, using solution combustion synthesis method, with urea as fuel. After optimizing the semiconductor properties, low-voltage TFTs were obtained by implementing a back-surface passivated 3-layer In:Ga:Zn 3:1:1 with a solution-processed high-к dielectric; AlOx. The devices show saturation mobility of 3.2 cm2 V−1 s−1, IOn/IOff of 106, SS of 73 mV dec−1 and VOn of 0.18 V, thus demonstrating promising features for low-cost circuit applications. [ABSTRACT FROM AUTHOR]

An advanced compact and analytical drain current model for the amorphous gallium indium zinc oxide (GIZO) thin film transistors (TFTs) is proposed. Its output saturation behavior is improved by introducing a new asymptotic function. All model parameters were extracted using an adapted version of the Universal Method and Extraction Procedure (UMEM) applied for the first time for GIZO devices in a simple and direct form. We demonstrate the correct behavior of the model for negative V DS , a necessity for a complete compact model. In this way we prove the symmetry of source and drain electrodes and extend the range of applications to both signs of V DS . The model, in Verilog-A code, is implemented in Electronic Design Automation (EDA) tools, such as Smart Spice, and compared with measurements of TFTs. It describes accurately the experimental characteristics in the whole range of GIZO TFTs operation, making the model suitable for the design of circuits using these types of devices. [ABSTRACT FROM AUTHOR]

In this work, we develop a simple and eco-friendly water-inducement method for high- k yttrium oxide (YO x ) dielectric. To prepare YO x thin films at low temperature, yttrium nitrate and deionized water were used as the source materials. No toxic organic materials were required in the YO x coating process. The YO x thin film annealed at 350 °C showed a low leakage current density of 2 × 10 −9 A/cm 2 at 5 MV/cm and a large areal-capacitance of 448 nF/cm 2 at 1 kHz. On the basis of its implementation as the gate dielectric, the fully-water-induced In 2 O 3 TFT based on YO x exhibited a high field-effect mobility of 15.98 cm 2 /Vs, excellent subthreshold swing of 75 mV/dec, an on/off current ratio of 6 × 10 6 , and a negligible hysteresis of 50 mV. The as-fabricated TFT operated at a low voltage (∼1.5 V) and showed high drain current drive capability, enabling oxide TFT with a water-induced high- k dielectric for use in backplane electronics for low-power mobile display applications. [ABSTRACT FROM AUTHOR]