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The high-performance ZnO thin-film transistors (TFTs) were fabricated on indium tin oxide glass with high-capacitance atomic layer deposition (ALD)-processed ZrO2 as the gate dielectric. The 5-nm ultrathin ZrO2 film showed a very high areal capacitance of 820 nF/cm2 at 20 Hz, a relatively high breakdown field of 14 MV/cm, and low surface root-mean-square (rms) roughness of 0.22 nm, making it possible for ZnO/ZrO2 TFT to not only be operated by an ultralow operating voltage of 1 V but also present a near theoretical limit subthreshold swing of 69 mV/dec. Furthermore, the ZnO TFT with a 5-nm ZrO2 gate dielectric exhibited excellent performance, such as a high Ion/Ioff of 107, large field effect mobility of 36.8 cm2/Vs, low-density of trapping states (${N}_{{\text {trap}}}$) of $1.6\times 10^{{11}}$ eV−1cm−2, and negligible hysteresis. In addition, the electron transport mode was built to explain the high mobility of nanocrystalline ZnO TFT. As a result, the ultralow operating voltage TFTs exhibited great potential for low-powered electronics applications. [ABSTRACT FROM AUTHOR]

We report stable and high performance amorphous indium‐gallium‐zinc oxide (a‐IGZO) thin‐film transistor (TFT) by using bulk‐accumulation (BA) and split active/source/drain layers. The a‐IGZO TFTs exhibit the mobility over 80 cm2/Vs and extremely stable under bias and mechanical stresses. We demonstrated a 4‐inch semitransparent AMOLED using the oxide TFT backplane with the gate driver integrated. [ABSTRACT FROM AUTHOR]

• F and Al co-doped ZnO (FAZO) films have been realized by RF magnetron sputtering. • Performance of FAZO film is better than the FTO and comparable to the ITO film. • High efficiency Perovskite solar cells have been succeeded using the FAZO films. ZnO films with excellent photoelectric properties have been realized in this study through low-concentration F-and-Al co-doping, conducted with radio-frequency magnetron sputtering. It has been demonstrated that the valence state of Al gradually changes from the incomplete oxidation state to the oxidation state, though the chemical valence states of F, O, and Zn are stable. The as-prepared films possess good performance with a mobility of ∼41.89 cm2/Vs, resistivity of ∼3.50 × 10−4 Ω cm, and an average transmittance over 90% in the range of 400–1200 nm. Moreover, the crystallinity of the films and effect of Al doping were further improved through post annealing. Consequently, the improved film mobility, carrier concentration, resistivity, and sheet resistance were, respectively, measured as 53.97 cm2/Vs, 5.18 × 1020 cm−3, 2.23 × 10−4 Ω cm, and 2.73 Ω/□. These films are, therefore, superior to the commercial F-doped SnO 2 (FTO) and comparable to the Sn-doped In 2 O 3 (ITO) films. High-performance perovskite with a conversion efficiency as high as 16.24% was achieved when the abovementioned optimized film was used as the front electrode. The reference perovskite solar cells that had commercial ITO and FTO as their front electrodes showed lower efficiency of 15.92% and 12.45%, respectively. [ABSTRACT FROM AUTHOR]

We report the thickness effect of amorphous silicon for the polycrystalline silicon (poly-Si) layer laterally crystallized by blue laser annealing (BLA) using 50 μs melting time. The grain size is much larger and full width at half-maximum of Raman intensity is lower compared to those of the poly-Si by excimer laser annealing. It is found that the average width of lateral grain is wider than 3 μm and full width of half maximum of Raman intensity for the BLA poly-Si with an optimum thickness of 90 nm is 3.32 cm−1. The p-type poly-Si thin-film transistor with 90 nm exhibits field-effect mobility of 161.91 ± 6.14 cm2/Vs and subthreshold swing of 227 ± 7 mV/dec. • High mobility TFT with 90 nm poly-Si on glass crystallized by blue laser using 50 μs melting time [ABSTRACT FROM AUTHOR]

Rock avalanches have an important impact on the geomorphological evolution of mountain landscapes. Rock avalanche-debris geometry holds important clues related to the processes of the disaster predisposition, occurrence and rapid runout of rock avalanche-debris flows. The morphological features of the debris of the Touzhai rock avalanche deposit in Southwest China are examined as a specific case with the help of three-dimensional laser scanning, polarization microscopy (for polished sections) and field-emission scanning electron microscopy (FESEM). The unexpectedly high roundness is the most impressive morphological characteristic of the Touzhai rock avalanche-debris, particularly that of sand-plus silt-sized particles. The shapes of 12 scanned metric-sized boulders are closer to cubes than to spheres. 90% of the 114 scanned subangular blocks with a mean particle diameter of 12.04 cm and an average specific surface area of 0.225 cm2/g fall into the spherical domain of Zingg's classification diagram according to their flatness ratio and elongation ratio, and the average sphericity of 0.798 further indicates that they are more akin to cubes compared with spheres. The average form factor of the 1201 sand-sized grains is 0.784 with a standard deviation of 0.044, indicating that they are nearly spherical, and the solidity ranging from 0.951 to 0.974 also strongly shows that these particles are close to smooth spheres. Most of the grains in the size range of <0.075 mm are sub-angular except slaty secondary clay minerals of <0.005 mm based on the visual estimation under FESEM. The detailed qualitative and quantitative contrasts between the morphometric characteristics of the Touzhai rock-avalanche debris and those of the fresh basalt fragments demonstrate that the geometry of the former is dominated by the pre-failure predesign in which the basalt, primary and secondary structures, unloading and weathering acted together. Weathering was the direct contributor to its high roundness. The dynamic fragmentation triggering newly generated ruptures during the post-failure motion was less important, which should be the case in some rock avalanches in other regions. The slope pattern of "large creeping main slide mass + lower intact locked segment" generalized according to this study should be applicable to some other rock avalanches worldwide, and can help the pre-event identification of the potential rock-avalanche sites. Our results support the hypothesis of "aerification of debris" to explain the high mobility of rock avalanches. Highly fragmented source rockmass with enough fine grains should be necessary for the occurrence of rock avalanches and long, rapid runout of the rock avalanche-debris flows. • A combination of 3D laser scanning, optical microscopy and FESEM is uniquely used. • The geometry of the debris from a large rock-avalanche deposit is quantified. • The studied debris has unexpectedly high roundness. • The high roundness was derived from of the predesign of the rock avalanche. • Some of the conclusions should be applicable to similar rock avalanches. [ABSTRACT FROM AUTHOR]

This paper reports the effect of the cation composition on the electrical properties of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) where atomic layer deposition (ALD) was used to deposit an a-IGZO channel layer. The In0.38Ga0.18Zn0.44O transistors at a 200°C annealing temperature exhibited 39.4 cm2/V·s field effect mobility (µFE), −0.12 V threshold voltage (VTH), 0.40 V/decade subthreshold gate swing (SS), and >107 ION/OFF ratio, corresponding to the state-of-the-art characteristics of transistors with a sputtered IGZO channel. Further enhancement of the μFE value was observed for the devices with a higher In fraction: the In0.45Ga0.15Zn0.40O transistor had a higher μFE value of 48.3 cm2/V·s, −4.06 V VTH, 0.45 V/decade SS, and >107 ION/OFF ratio. The cation composition dependence on the performance of the a-IGZO TFTs was explained by analysing the density-of-state (DOS) distribution for the corresponding devices using the experimental independent variable (IV) and theoretical Technology Computer-aided Design (TCAD) simulation. [ABSTRACT FROM AUTHOR]

We report stable and high performance a‐IGZO TFT by using bulk‐accumulation (BA) and split active /source/drain layers. The a‐IGZO TFTs exhibit the mobility over 80 cm2/Vs and extremely stable under bias and mechanical stresses. We demonstrated a 4‐inch semi‐transparent AMOLED using the oxide TFT backplane with the gate driver integrated. [ABSTRACT FROM AUTHOR]

We report the effect of the cation composition on the electrical performance of amorphous indium gallium zinc oxide (a‐IGZO) thin‐film transistors (TFTs) which was deposited by atomic layer deposition (ALD). The In/In+Ga ratio of a‐IGZO TFT was increased, enhancement of the field‐effect mobility (µFE) value was observed. The device with a higher In/In+Ga ratio: the In0.45Ga0.15Zn0.40O transistor showed a higher µFE value of 48.3 cm2/Vs, VTH of −4.06 V, SS of 0.45 V/decade, and ION/OFF ratio of > 107. Simultaneously, Density of States (DOSs) profile in a forbidden band gap of the a‐IGZO semiconductor were extracted based on the Meyer‐Neldel rule (MN rule) to obtain an insight into the cation composition dependent performance of a‐IGZO TFTs. [ABSTRACT FROM AUTHOR]

This work developed a back‐channel‐etched In‐Ga‐Zn‐Sn‐O (IGZTO) thin‐film transistor (TFT) with a high mobility of 41 cm2/Vs by optimizing both the IGZTO composition and the fabrication process. Furthermore, an effective mobility of 99 cm2/Vs was achieved for an IGZTO‐TFT with a dual‐gate structure. [ABSTRACT FROM AUTHOR]

We report the high performance top gate IGZO‐TFT for OLED display. By optimizing the conditions of process, we fabricated the transistor with mobility from 7 to 32 cm2 /Vs with enhanced threshold voltage. They also have reliability PBT/NBT enough to use application. Finally, the prototype 12.3" ultrawide flexible OLED display was successfully demonstrated. [ABSTRACT FROM AUTHOR]

• Milestones are focus-reviewed by highlighting most remarkable conjugated polymers. • Emerging charge-transport models based on short-range order are summarized. • Recent experimental progress based on short-range order is highlighted. The booming of classic semicrystalline polymers has led to the assumption and thus design guidelines that long-range order is a prerequisite to endow conjugated polymers with high charge carrier mobility. Consequently, tremendous research effort has been devoted to increasing the crystallinity of conjugated polymers, as a principal strategy to improve the solid-state long-range charge-transport properties. Indeed, noticeable progress in the polymer performance has been witnessed. However, only a limited level of crystallinity can be achieved due to the inherently disordered nature of the polymer chains, resulting in the bottlenecks of the charge carrier mobility of conjugated polymers. Encouragingly, the recent reports of substantially disordered, high-performance conjugated polymers have opened a new route for achieving efficient charge transport, and lead to new waves of progress in the field of organic electronics. The universal observation of short-range order (in the form of aggregation) in the emerging class of poorly ordered conjugated polymers seems to suggest that local order is sufficient for efficient charge transport, and that extended long-range crystallinity is not essential. This review discusses the molecular origin of the high mobilities observed in the state-of-the-art low-crystalline conjugated polymers, especially highlighting the crucial role of short-range order. [ABSTRACT FROM AUTHOR]

Graphical abstract A channel-restricted meniscus self-assembly (CRMS) method is developed for wafer-scale, highly uniform, aligned growth of organic semiconductor single crystals (OSSCs). Field-effect transistors (FETs) made from the OSSC arrays exhibit a high average mobility of up to 30.3 cm2 V−1 s−1 with good uniformity among devices. This method is general for the growth of various OSSC arrays, facilitating the applications of OSSCs in large-area, high-performance organic electronic devices. Abstract Organic semiconductor single-crystal (OSSC)-based field-effect transistors (FETs) with high mobility and small device-to-device variation enable OSSCs to be adapted for practical applications. Research attention has recently been focused on developing simple ways of fabricating large-area OSSC arrays by means of solution-coating techniques. However, the lack of control of the meniscus front, where the nucleation and growth of organic crystals occur, leads to inconsistent crystal alignment and consequently induces large variation in device performance. Here, we propose a universal strategy, termed the channel-restricted meniscus self-assembly (CRMS) method to fabricate ultrahigh-mobility, uniform OSSC arrays. The microscale photoresist channels used in this method produce a confinement effect to reduce the size of the meniscus, enabling the homogeneous nucleation of OSSCs at the meniscus front. Meanwhile, the dip-coating process ensures consistent molecular packing in the OSSCs and thus guarantees their highly uniform electrical properties. Using 2,6-diphenylanthracene as an example, wafer-scale (>2 inch) OSSC arrays with very small size variations (10%) are successfully prepared, which is very difficult to achieve by using the previously reported methods. As a result, field-effect transistors (FETs) based on the OSSC arrays show a high average hole mobility of up to 30.3 cm2 V−1 s−1 with good uniformity among devices. This method is general for the growth of various OSSC arrays, facilitating the applications of OSSCs in large-area, high-performance organic electronic devices. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau is a landslide-prone area in Southwest China. A large-scale ancient landslide named Luanshibao Landslide on the eastern margin of the Tibetan Plateau is described in this paper, based on field investigation and satellite image interpretation. The geological setting and morphometric properties of the landslide are presented. Especially, the hummocky landscape, a prominent feature in the deposit area, is described. The total run-out distance of this landslide is 3910 m and the maximum velocity is estimated to be 36.6 m/s. The angle of reach is analysed as the index expressing the mobility of the landslide. Its value is about 12 degrees, indicating the high landslide mobility. Field observation shows that this landslide was most likely triggered by an earthquake, and the seismic acceleration capable to induce this landslide is estimated to be 0.36 g. This landslide might have changed the course of the Litang River. [ABSTRACT FROM AUTHOR]

Thin films of the polymeric semiconductor 2,5-bis (3-hexadecylthiophen-2-yl) thieno (3,2-b) thiophene obtained by compression with a glass blade exhibit high-carrier mobility. This enhanced performance has been attributed to the uniaxial alignment of the polymer molecules, although such alignment has not yet been demonstrated experimentally. In the present study, the local alignment of the polymer was estimated using transmission electron diffraction. The diffraction spots corresponding to π − π stacking layers (along the b -axis) showed an arc-like intensity distribution along with angles of 11.6°, 15.8° and 25.4° for selected areas having diameters of 70, 140 and 280 nm, respectively. This variation of the arc angle with diameter indicates that the polymer chains were arranged in a gentle winding state, with an average radius of curvature of ~630 nm. We conclude that, as expected, the high-carrier mobility of the polymer is related to its uniaxial alignment. [ABSTRACT FROM AUTHOR]

Abstract Fluorine and aluminum co-doped ZnO (FAZO) films were deposited on glass substrates by RF magnetron sputtering. The effects of the substrate temperature (T sub) on the structural, morphological, electrical, and optical properties of the films were investigated by X-ray diffraction analysis, atomic force microscopy, photoluminescence spectroscopy, Hall effect measurement, and ultraviolet–visible–near infrared spectrophotometry. All the thin films showed typical wurtzite structure with the c axis preferentially oriented perpendicular to the substrate. With increasing T sub , the grain size shows a parabolic-like enhancement; the film surface became relatively smooth and dense, and the crystallinity was also improved. At T sub = 320 °C, the films showed the best electrical properties, with a resistivity of 3.53 × 10−4 Ω cm, Hall mobility of 39.33 cm2/V s, and carrier concentration of 4.50 × 1020 cm−3. An optical transmittance of more than 80% in a wide wavelength range from 400 to 1200 nm was also achieved. Perovskite solar cells employing the FAZO film had a higher power conversion efficiency than reference cells using F-doped SnO 2 and Sn-doped In 2 O 3 , demonstrating its suitability for application in high-efficiency solar cells. Graphical abstract fx1 Highlights • High mobility, low resistivity and wide spectral transmittance FAZO films were deposited on glass substrates. • Perovskite solar cells employing FAZO film shows higher performance than reference cells using FTO and ITO films. • Good electrical and optical properties as well as the application for perovskite solar cells show that FAZO films have wide application prospects in high-efficiency solar cells. [ABSTRACT FROM AUTHOR]

Abstract Future flexible electronic systems require memory devices combining low power consumption and mechanical bendability. However, high programming/erasing (P/E) voltages, which are universally required to switch the storage states in previously reported ferroelectric organic field-effect transistor (Fe-OFET) nonvolatile memories (NVMs), severely prevent their practical applications. In this work, we develop a novel route to achieve a low-voltage programmable/erasable flexible Fe-OFET NVM. Ferroelectric terpolymer poly(vinylidene-fluoride-trifluoroethylene-chlorotrifluoroethylene) [P(VDF-TrFE-CTFE)], rather than the conventional ferroelectric copolymer poly(vinylidene-fluoride-trifluoroethylene) [P(VDF-TrFE)], is used as the gate dielectric. The low coercive field of P(VDF-TrFE-CTFE) is the main contribution to the low-voltage operation in the Fe-OFET NVM, even with a relative thick ferroelectric gate dielectric layer. By depositing a long-chain alkane molecule Tetratetracontane (TTC) as the passivation layer on the surface of P(VDF-TrFE-CTFE) film, the layer-by-layer growth mode of semiconductor pentacene is obtained, which results in a large crystalline grain and good interface morphology at the channel/dielectric. Therefore, the mobility of Fe-OFET NVMs is greatly improved. As a result, a high performance flexible Fe-OFET NVM is achieved, with a low P/E voltage of ±15 V, high mobility up to 0.5 cm2 V−1 s−1, reliable P/E endurance property over 1000 cycles, stable data storage retention capability over 6000 s, and excellent mechanical bending durability without visible degradation after 2000 repetitive tensile bending cycles at a small curvature radius of 4.0 mm. Graphical abstract Image 1 Highlights • Low-voltage programmable/erasable flexible Fe-OFET NVM is achieved. • Ferroelectric P(VDF-TrFE-CTFE) with a low coercive field is used as gate dielectric. • The mechanism for the improvement of mobility in the Fe-OFET is researched. • Excellent mechanical bending durability is also achieved in the memory. [ABSTRACT FROM AUTHOR]

Abstract Its high electron mobility makes hydrogen doped indium oxide (IOH) a promising transparent conductive oxide for photovoltaic and other applications. We report on a deposition process for IOH that is attractive for industrial application, using large area pulsed direct current (DC) magnetron sputtering and annealing in air. Structural, optical and electrical properties as well as stability of films annealed in air were assessed and compared to vacuum annealed films. Critical factors were found to be water and oxygen partial pressures during the sputter process, which, when chosen inappropriately, can cause a low density film structure, enhancing diffusion of atmospheric species into the indium oxide layer during crystallization in air. This leads to a lower charge carrier density of air annealed films compared to vacuum annealed films. We introduce a bi-layer stack to reduce diffusion processes during air annealing and thus improve the charge carrier density without adversely affecting the electron mobility or optical absorption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Here, through constructing GaSe/SnSe heterojunction, we found the hole and electron mobility can reach 5916 and 483.53 cm2V−1s−1, 846 and 1.4 times higher than mono-SnSe. • Forming type-II band alignment. • Broaden absorption spectrum to the near-infrared spectrum through biaxial strain. • Decrease band gap through the electrical field. GaSe is widely used in optoelectronics, and its nanosheets exhibit excellent on–off current ratios and photoresponsivity. However, its large band gap limits visible light absorption. Here, through constructing GaSe/SnSe heterojunction, we found the hole and electron mobility can reach 5916 and 483.53 cm2V−1s−1, 846 and 1.4 times higher than mono-SnSe, respectively, due to it forming type-II band alignment reducing the recombination. In addition, the absorption spectrum can be broadened to the near-infrared spectrum (the band gap can be decreased to 0) through a biaxial strain or electrical field. This work provides a method to highly improve the efficiency and application scope of GaSe optoelectronic devices. [ABSTRACT FROM AUTHOR]

• We adjust the electrolyte ion ratio to investigate the effects of electrolyte ion ratio on the electrical characteristics. • We found that changing the electrolyte ion ratio will change the electrical, morphological and surface properties of CuSCN. • We found that when the electrolyte ion ratio E SCN/Cu is 2, there is the highest mobility. When optimizing the electrolyte ion ratio and depositing an excellent characteristic CuSCN thin film would offer a significant promising opportunity for CuSCN which will be widely used in optoelectronic device. In this kind of work, CuSCN films are eventually prepared using electrodeposition method and how electrolyte ion ratio influences the morphology and electrical properties of CuSCN thin films and the corresponding mechanisms are studied in detail. The thin films which are deposited with electrolyte ion ratio Cu: SCN 1:2 (named as CuSCN (1:2)) generally exhibited more excellent mobility which in-fact solve the CuSCN biggest challenge: low conductivity compared to other P-type materials which makes it low mobility. The mobility of non-stochiometric CuSCN films with E SCN/Cu ratio of 2 is gradually increased by 228 times as compared with that of stochiometric films. The phenomenon can be usually ascribed to the Cu vacancy in CuSCN (1:2) which is entirely influenced by the microstructure of CuSCN films. The valance band of CuSCN (1:2) is 4.77 near ITO work function (4.8 eV). It can as well reduce the energy barrier between ITO and CuSCN which can increase the efficiency of the device such as photodetector and solar-cell which use ITO and CuSCN as the electrode and P-type material. Up to the core knowledge of the author, it is the first report about the properties of non-stochiometric α-CuSCN films. [ABSTRACT FROM AUTHOR]

One technology bottleneck for system‐on‐panel (SoP) is the lacking of high‐performance p‐type thin‐film transistor (pTFT). Using high dielectric‐constant (high‐κ) gate materials with optimized processes, high hole and electron field‐effect mobility of 7.6 and 345 cm2/Vs were measured in pTFT and nTFT, respectively. These high mobility devices on SiO2 are the enabling technology for SoP and crucial for three‐dimensional brain‐mimicking integrated circuit (IC)‐ the technology trend for IC after reaching the quantum‐mechanical limit soon. [ABSTRACT FROM AUTHOR]

Development of p‐type inorganic semiconductors for high performance thin‐film transistor (TFT) can be an essential ingredient for next‐generation display applications which requires a low power consumption. However, the conventional p‐type oxide semiconductors exhibit the poor electrical characteristics, which is mainly attributed to the inefficient conduction path formation from oxygen 2p orbitals. Here, we report a new p‐type material, tin oxyselenide (SnSeO) semiconductors for high performance p‐channel TFTs. The SnSeO was designed with the concept that valence band maximum (VBM), hole conduction path, becomes delocalized by hybridizing selenium 4p and tin 5s orbitals. The SnSe0.56O0.44 thin‐film exhibited the highest Hall mobility of 15.0 cm2 V‐1 s‐1 and hole carrier density of 1.2 x 1017 cm‐3. In addition, the SnSe0.56O0.44 TFT showed the excellent field‐effect mobility of 5.9 cm2 V‐1 s‐1 and current modulation ratio of 3.0 x 102. This high mobility is explained by the low hole effective mass through valence band engineering, which was confirmed by density functional theory calculation. Moreover, complementary metal oxide semiconductor (CMOS) inverter using the p‐type SnSe0.56O0.44 with n‐type IGZO showed excellent intrinsic gain of 15.7. This anion hybridization can provide a facile route to the realization of a high performance p‐channel TFT for next‐generation displays. [ABSTRACT FROM AUTHOR]

W opracowaniu przedstawiony został problem niezgodności kinematycznej hydrostatycznych układów napędowych pojazdów wysokiej mobilności oraz jej wpływ na występowanie niekorzystnego zjawiska mocy krążącej. Ponadto zaprezentowane zostały rozważania teoretyczne dotyczące zdolności kompensacji niezgodności kinematycznej przez hydrostatyczny układ napędowy na podstawie badań z wykorzystaniem charakterystyk statycznych.

High-mobility orthogonal frequency division multiplexing(OFDM)systems suffered severe inter-carrier interference(ICI)from Doppler spreading.On the basis of the characteristics of wireless propagation in practical scenarios,a method which employed the WINNER Ⅱ channel model to represent the practical wireless channel and an antenna array as the receiver to eliminate ICI in space-domain was proposed.The direction of arrival estimation algorithm and the beamforming network were used to separate the received signals in space-domain.Multi-beam diversity gain was obtained finally by means of combining the signals which have been compensated for Doppler frequency shifts(DFS)respectively.Simulation results demonstrate that the proposed method not only effectively reduces ICI and the error floors,but also obtains a 5～7 dB signal-to-interference gain over systems without use of the proposed method.

Top-gate self-aligned structured oxide thin-film transistors (TFTs) are suitable for the backplanes of high-end displays because of their low parasitic capacitances. The gate insulator (GI) deposition process should be carefully designed to manufacture a highly stable, high-mobility oxide TFT, particularly for a top-gate structure. In this study, a nanometer-thick Al 2 O 3 layer via plasma-enhanced atomic layer deposition (PE-ALD) is deposited on the top-gate bottom-contact structured oxide TFT as the interface tailoring layer, which can also act as the hydrogen barrier to modulate carrier generation from hydrogen incorporation into the active layer of the TFT during the following process such as postannealing. Al-doped InSnZnO (Al/ITZO) with an Al/In/Sn/Zn atomic ratio composition of 1.7:24.3:40:34 was used for high mobility oxide semiconductors, and an Al 2 O 3 /Si 3 N 4 bilayer was used for the GI. The degradation issue due to the excellent barrier characteristics of Al 2 O 3 and Si 3 N 4 can be minimized. An oxide TFT fabricated without the interface tailoring layer exhibits conductor-like characteristics owing to the excessive carrier generation by hydrogen incorporation. However, TFTs with additional interface layers exhibit reasonable characteristics and distinct trends in electrical characteristics depending on the thicknesses of the interface layers. The optimized devices exhibit an average turn-on voltage ( V on /(V s) of high mobility and 0.09 V/dec of subthreshold swing value. The interfaces between the active layer and hydrogen barriers were investigated using a high-resolution transmission electron microscope, contact angle measurement, and secondary ion mass spectroscopy to reveal the origin of the trends in properties between the devices. The top-gate device with a hydrogen barrier using the four-cycle deposition exhibits optimum electrical characteristics of both high mobility and good stability with only a 0.04 V shift of 2 under positive-bias temperature stress (PBTS). We realize a high-end, self-aligned TFT with high mobility [34.7 cm V on under positive-bias temperature stress (PBTS). We realize a high-end, self-aligned TFT with high mobility [34.7 cm 2 /(V s)] and negligible V on shift of -0.06 V under PBTS by applying a subnanometer hydrogen barrier.

Quasi-2D (q2D) conjugated polymers (CPs) are polymers that consist of linear CP chains assembled through non-covalent interactions to form a layered structure. In this work, the synthesis of a novel crystalline q2D polypyrrole (q2DPPy) film at the air/H 2 SO 4 (95%) interface is reported. The unique interfacial environment facilitates chain extension, prevents disorder, and results in a crystalline, layered assembly of protonated quinoidal chains with a fully extended conformation in its crystalline domains. This unique structure features highly delocalized π-electron systems within the extended chains, which is responsible for the low effective mass and narrow electronic bandgap. Thus, the temperature-dependent charge-transport properties of q2DPPy are investigated using the van der Pauw (vdP) method and terahertz time-domain spectroscopy (THz-TDS). The vdP method reveals that the q2DPPy film exhibits a semiconducting behavior with a thermally activated hopping mechanism in long-range transport between the electrodes. Conversely, THz-TDS reveals a band-like transport, indicating intrinsic charge transport up to a record short-range high THz mobility of ≈107.1 cm 2 V -1 s -1 ., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Abstract Construction solid waste (CSW) landslides are always characterized by high mobility, and thus pose much danger to surrounding residents and buildings. In this study, a back in situ analysis of the catastrophic CSW landslide occurred in Shenzhen in December 2015 is presented, in which the motion-accumulation evolution process of the landslide and damage to structures are reproduced, and reasonable agreement between the simulation and actual conditions is obtained. In landslide process modeling, a depth-averaged model that can undergo dilation and contraction during deformation is adopted to simulate the behavior of the landslide assuming different conditions of initial solid volume fraction. The results show that a small initial solid volume fraction of a water-laden landslide undergoes small resistance caused by dilatancy. On the basis of landslide process analysis, the fluid–solid interaction is decoupled and considered to be a one-way action of the landslide on structures, which is reflected in the form of impact force. Structural response is evaluated by 3D finite element modeling. The failure process presents a type of plastic hinge formation at the beam–column connection positions, followed by local destruction of the impacted columns, and final structural failure is the cumulative result of this damage over time. This integrated approach could be implemented in quantitative risk assessment procedures pertaining to landslides. Highlights • A depth-averaged model considering dilatancy effect is adopted to describe the high mobility of CSW landslide. • The failure analysis of structure is based on landslide movement process, which indicates the time effect of damage. • Reasonable agreement between simulation and observed conditions is obtained. [ABSTRACT FROM AUTHOR]

This letter presents high-mobility thin-film transistors (TFTs) based on InGaZnO by a novel infrared (IR) radiation activated low-temperature solution process. A high mobility of over 60 cm2V−1s−1, an ${I}_{\mathrm{\scriptscriptstyle ON}}/{I}_{\mathrm{\scriptscriptstyle OFF}}$ ratio of 106, and a decreased operating voltage of 4 V were achieved at 230 °C. This mobility was four times higher than that of a device by high-temperature (450 °C) annealing, and was comparable to those of oxide TFTs previously produced via vacuum or high-temperature processes. The synergistic IR radiation and thermal energy mechanism resulted in more effective removal of precursor impurities, a more extensive metal-oxygen lattice, and more oxygen vacancies to serve as charge carriers, which contributed to the much higher performance achieved with IR radiation. Moreover, the IR-processed devices exhibited excellent operational stability with a small ${V}_{\textsf {th}}$ shift under bias stress. Our results may provide new low-temperature solution routes to high-performance TFTs. [ABSTRACT FROM AUTHOR]

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The ever increasing requirements in wireless communications have led to the search for unexploited correlations that could improve channel estimation and tracking. Kalman filtering (KF) has been proposed to exploit several such correlations, e.g., the time correlation in each tap in a multipath channel. When making full use of this correlation, however, a capital disadvantage of KF is its weak performance in the face of a significant, occasional nonlinearity, such as the potential birth of a new tap in a multipath channel or an active tap's death. These nonlinearities are typical for vehicular applications. So far, solutions proposed to this birth-death nonlinearity problem have been shown to be computationally prohibitive. In this paper, a simplified detection framework is introduced and a computationally inexpensive simplified maximum a posteriori estimator is derived. Under low to medium SNR conditions, simulations show the channel tracking error can be approximately halved (versus simple KF) by this novel estimator in orthogonal frequency division multiplexing systems. [ABSTRACT FROM AUTHOR]

Millimeter-wave (mmWave) systems use directional beams to support high-rate data communications. Small misalignment between the transmit and receive beams (e.g., due to the mobility) can result in a significant drop of the received signal quality, especially in line-of-sight communication channels. In this paper, we propose and evaluate high-resolution angle tracking strategies for wideband mmWave systems with mobility. We custom design pairs of auxiliary beams as the tracking beams, and use them to capture the angle variations, toward which the steering directions of the data beams are adjusted. Different from conventional beam tracking designs, the proposed framework neither depends on the angle variation model nor requires an on-grid assumption. For practical implementation of the proposed methods, we examine the impact of the array calibration errors on the auxiliary beam pair design. Numerical results reveal that by employing the proposed methods, good angle tracking performance can be achieved under various antenna array configurations, channel models, and mobility conditions. [ABSTRACT FROM AUTHOR]

In this article, we will measure individuals' and groups' aptitude for movement and consider them relative to their living environment by developing a typology of motility. This will help highlight both the range and variety of skills for being mobile, and the social and spatial inequalities associated with them. We will address this question based on the panel data from the Job Mobilities and Family Lives research study (hereafter referred to as JobMob) conducted in four European countries (Germany, France, Spain and Switzerland) in 2007 and 2011. This article focuses on forms of work-related mobility and thus concerns working-age people. [ABSTRACT FROM AUTHOR]

Nowadays, the microwave photonics (MWP) concept has been evolved from laboratory tests to practical applications, and related techniques have been widely deployed in many fields including such as wireless communications, medicine, sensing, radars, electronic warfare, and space explorations. In this paper, we concentrate on the featured applications of MWP in the high-speed railways (HSRs), an emerging field and massive market, and an overview about our recent work is presented. The radio-over-fiber based wireless communications in high-mobility scenarios, photonic-assisted electromagnetic interference detection along HSR lines, and fiber sensing for safety protection of railways are investigated systematically in our group. Experiments are then performed to verify the basic functionalities of the three MWP-enabled systems mentioned above. In particular, field trials have been successfully implemented along two in-service HSR lines located in Southwest China, i.e., the Chengdu–Chongqing and the Chengdu–Mianyang–Leshan HSR lines. With these results and achievements, we can expect more MWP-enabled striking applications in the HSR field in near future. [ABSTRACT FROM AUTHOR]

This letter investigates the sparse channel estimation approach for multiple input multiple output systems in high mobility scenarios. The large quantity of channel estimation coefficients is significantly reduced by taking advantage of both the channel sparsity in time-angle domain and the basis expansion model for time-varying channel. After the establishment of the structured compressive sensing model, a Newton auxiliary block orthogonal matching pursuit algorithm is put forward to recover the channel. It is illustrated in the numerical simulation results that the proposed approach has excellent performance and outperforms the traditional counterparts. [ABSTRACT FROM AUTHOR]

A new transparent p-type oxide semiconductor (POS) is reported, Cu2SnS3-Ga2O3, having high Hall mobility of 36.22 cm2 V-1s-1, and high work function of 5.17 eV. The existence of Cu2SnS3 and Ga2O3 phases in the film is confirmed by X-ray photoelectron spectroscopy results and the Cu2SnS3 shows polycrystalline structure according to Raman spectrum and X-ray diffraction analysis. The transparent Cu2SnS3-Ga2O3 exhibits the carrier concentration of 5.86 × 1016 cm-3, and electrical resistivity of 1.94 Ω·cm. The transparent POS is applied to green quantum light-emitting diodes (QLEDs) as a hole injection layer (HIL) because of its high work function. The QLED exhibits the maximum current efficiency of 51.72 cd A-1, power efficiency of 31.97 lm W-1, and external quantum efficiency (EQE) of 14.93%, which are much higher than the QLED using polyethylene dioxythophene:poly(styrenesulfonate) HIL exhibiting current efficiency of 42.66 cd A-1, power efficiency of 20.33 lm W-1, and EQE of 12.36%. The Cu2SnS3-Ga2O3 developed in this work can be widely used as a transparent and conductive p-type oxide for thin-film devices. [ABSTRACT FROM AUTHOR]

Colonoscopes are one The first two authors contributed equally to this workof the best tools to detect colorectal cancer despite their several drawbacks. In order to solve the limitations of conventional colonoscopes and detect cancer more efficiently, robotic colonoscopes and capsule endoscopes have been proposed. However, active capsule endoscopes require expensive control systems, and they have functional limitations due to their small volumes. In addition, robotic colonoscopes fail to achieve sufficient mobility, resulting in longer colonoscopy times than with conventional colonoscopes. Therefore, the present study proposes a simple, reliable reel mechanism-based robotic colonoscope that achieves high mobility. Because the robot is operated by a reel with an external high-capacity motor, enhanced mobility is attained regardless of environment. Moreover, the proposed robotic colonoscope allows for the inclusion of an instrument channel, unlike previously reported robotic colonoscopes. A theoretical analysis is implemented to confirm the mobile performance. The analysis results are compared with the results of a locomotion test in a urethane tube (diameter = 28 mm). Ultimately, the robot achieves high mobility (66.04 ± 5.97 mm/s with a motor speed of 200 r/min), and the error between the theoretical and experimental results is less than 1%. Furthermore, an in-vitro test in an excised porcine colon is performed to verify the feasibility of the locomotion in a large intestine. In straight and sloping paths (30° and 45°), the robot travels at 21.11 ± 1.69 mm/s, 18.77 ± 3.42 mm/s, and 8.76 ± 1.68 mm/s, respectively, with a motor speed of 150 r/min. This is within the reliable operation range for colonoscopies. [ABSTRACT FROM AUTHOR]

We propose in this article, a Linear Minimum Mean Squares Error-Support Vector Machine regression (LMMSE-SVR) method which is employed high-speed 3GPP Long Term Evolution (LTE) downlink coded channel estimation environment. LMMSE-SVR approach is applied to track and estimate the fast fluctuations caused by Doppler effect of a 3GPP realistic Extended Vehicular A model (EVA) channel. We integrate in this contribution both channel estimation at pilot symbols and interpolation at data symbols into the LMMSE-SVR process with and without turbo coding scheme. Bit Error Rate (BER) performance of our channel environment estimation proposal is validated via simulation of LTE downlink system for both coded and uncoded high-speed scenarios with normal and extended Cyclic Prefix (CP) modes. [ABSTRACT FROM AUTHOR]

Recent studies on organic thin-film transistors (OTFTs) have reported high mobility values, but many of them showed non-ideal current-voltage characteristics that could lead to the overestimation of the mobility values. In this study, the non-ideal transistor behavior was briefly investigated by considering the effect of charge injection, and a method of overcoming the effect was developed. Correspondingly, various charge injection layers were developed, and their effects on the modification of metal contacts, including work function tuning and interfacial doping, were studied. The materials that had been coated formed a good metal-semiconductor interface through fine manipulation in the wetting and dewetting of the selected liquid. With such electrodes, the OTFTs were fabricated at room temperature and exhibited almost ideal transistor behavior in terms of the current-voltage characteristics, featuring high (over 10 cm2/Vs) field-effect mobility. [ABSTRACT FROM AUTHOR]

We have developed stable and high performance etch‐stopper (E/S) a‐IGZO TFT by using split oxide semiconductor layer. The a‐IGZO TFTs exhibit high mobility over 70 cm2/Vs and extremely stable under positive bias temperature stress. In this work we demonstrated a 4 inch transparent AMOLED using oxide TFT backplane with split active layer, where the gate driver is integrated. [ABSTRACT FROM AUTHOR]

The self‐compensating pixel circuit and the gate driver are fabricated with high mobility (~50cm2/Vs) oxide TFTs. In order to improve operating margin against negative shift of Vth in GIP circuit, the circuit utilizes two low‐voltage‐level signals. Also, the design of the EM driver to be controlled by the scan driver reduces the bezel size. Our 5.5‐in. FHD OLED display panel on PI substrate shows good uniformity and long‐term stability with saturation behavior of clamping voltage in GIP circuit under operation at 60°C for over 1,000 hours. [ABSTRACT FROM AUTHOR]

This letter reports the fabrication of high-performance amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) via atomic layer deposition at a substrate temperature of 250 °C. The film thickness of In2O3, Ga2O3, and ZnO varied linearly with the number of deposition cycles. The cation composition of the IGZO film was controlled by an alternate stacking of In2O3, Ga2O3, and ZnO atomic layers. The fabricated a-IGZO TFTs exhibited a high electron mobility of 22.1 cm2/Vs, threshold voltage of 2.41 V, subthreshold gate swing of 0.30 V/decade, and an ${I}_{{ \mathrm{\scriptscriptstyle ON}}/{ \mathrm{\scriptscriptstyle OFF}}}$ ratio of $> \textsf {1} \times \textsf {10}^{\textsf {8}}$. [ABSTRACT FROM AUTHOR]

In this paper, we propose an ultrathin SiGe shell channel p-type FinFET for sub-10-nm technology nodes. Owing to the large valence band offset (VBO or ΔEv) between SiGe shell and Si fin, a hole quantum well is configured in the high-mobility SiGe region as the major conduction path. The proposed device is optimally designed and characterized in dc and ac. Here, high-κ/metal gate is adopted for strong gate controllability and the high degree of freedom in threshold voltage (Vth) adjustment. For a high reliability, modeling of the mobility (μ) and saturation velocity (vsat) is carried out for different Ge fractions (x). The Eg and VBO are also determined for different x from empirical data. With the set of modeled values and various quantum-mechanical models, the proposed device has been simulated through rigorous 3-D technology computer-aided design simulation. The designed device shows a high scalability reaching down to Lg = 5 nm. At Lg of 5 nm with a driving voltage (VDD) of -0.5 V, a current gain cutoff frequency (fT) = 368.88 GHz, dynamic power = 0.055 fJ/μm, and an intrinsic delay (τ) = 0.37 ps are achieved. This is confirmed by the potential low-power and high-speed operations with a strong gate controllability. [ABSTRACT FROM AUTHOR]

A thermally stable Ca-doped CuOx (CuCaOx) diffusion barrier to prevent the migration of Cu to amorphous InGaZnO (a-IGZO) was developed by reactive sputtering and subsequent annealing. Insertion of a 5-nm-thick CaCuOx between the Ca-dopedCu (CuCa) and a-IGZO channel films in the source/drain contact regions provided the resulting transistors with superior charge transport and lower trap density compared to the diffusion barrier-free CuCa/a-IGZO transistors. The fabricated a-IGZO transistors with the CuCa/CuCaOx stack contact exhibited a high mobility of 20.8 cm²/V ⋅ s and an Ion/off ratio of 108. Simultaneously, very stable behavior against the external positive/negate gate bias stress was observed for the a-IGZO thin-film transistors with the CuCa/CuCaOx stack contact. This was attributed to suppression of Cu-related acceptor-like traps due to the conformal formation of CuCaOx film with excellent barrier properties. [ABSTRACT FROM AUTHOR]

We review in this talk the highly stable, high performance E/S a‐IGZO TFT on plastic substrate by using split active and S/D electrodes. The TFTs exhibit high mobility of 74 cm2/Vs and extremely stable behavior under bias‐stress and mechanical stress. The TFT process is same as conventional one with only design change. Therefore, this technology can be used for the manufacturing of flexible and bendable AMOLED on plastic substrate [ABSTRACT FROM AUTHOR]

We present high-mobility back channel etch Al–In–Zn–Sn–O/In–Zn–O (IZO) double-layer channel thin-film transistors (TFTs). The field-effect mobility of 53.2 \textcm^2/\textV \cdot \texts , threshold voltage of 0.5 V, and subthreshold swing of 0.15 V/decade were obtained with a thin IZO-inserted double-layer channel TFT. The positive bias stability was improved with an IZO-inserted double-layer channel. We fabricated 13-stage ring oscillators, which exhibited an oscillating frequency of 296 kHz at V \text {DD} = {20} . These results demonstrate that the proposed double-layer channel oxide TFT can be used for demanding applications such as backplane devices for ultrahigh resolution display. [ABSTRACT FROM AUTHOR]

Abstract: Perovskite solar cells have delivered power conversion efficiency beyond 22% in less than seven years, implying the potential for the paradigm shift of low‐cost photovoltaics with high efficiency and low embedded energy. Besides the “perovskite fever,” the development of new hole transport materials (HTM), especially dopant‐free HTMs, is another research hotspot. This is because the currently used HTMs, such as spiro‐OMeTAD derivatives, require additional chemical doping process to ensure sufficient conductivity and proper ionic potential level for efficient hole transport and collection. However, the commonly used dopants are volatile and hygroscopic which not only increase the complexity and cost of device fabrication but also deteriorate the device stability. So far, there have been several reviews on new HTMs, but review or analysis on dopant‐free HTMs is scarce. In this review, all reported dopant‐free HTMs are categorized into four primary different types and lessons will be learned during the separate discussions. The stability test behavior of all the intrinsic HTMs will be evaluated directly. In the end, the correlations between the properties of the intrinsic HTMs and parameters of the devices will be plotted to shed light on the future direction of development of this field. [ABSTRACT FROM AUTHOR]

Abstract: Transparent p‐type conductive γ‐CuI thin films typically exhibit unexpectedly high hole mobilities in the range of 10 cm2 V−1 s−1 even when heavily textured. To explain this phenomenon, the transport properties of such thin films are investigated. The temperature‐dependent resistivities of the textured (111)‐oriented films with different carrier concentration are fitted using the fluctuation‐induced tunneling conductivity (FITC) model in series with a power law. The FITC model describes barriers at the grain boundaries whereas the power law considers the scattering in the metallic interior of the grains. Magnetoresistance measurements performed on a reactively DC‐sputtered thin film at low temperatures (T < 8 K) suggest a 2D weak antilocalization effect with phase coherence lengths of about 50 nm. This is corroborated by a typical logarithmic temperature dependence of the zero‐field conductance. An n‐type inversion layer or a defect band at the interfaces of the grains as origin of the 2D carrier system and the barriers at the grain boundaries is proposed. This leads to a conclusive description of the electrical transport properties of γ‐CuI thin films and explains the high hole mobilities which are due to a suppressed backscattering at the grain boundaries in the presence of tunneling channels. [ABSTRACT FROM AUTHOR]

The low mobility is a primary issue to prevent the practical application of the ferroelectric organic field-effect transistor (Fe-OFET) nonvolatile memory (NVM). In this paper, we propose a route to resolve this issue by inserting an ultrathin AlOX layer between the semiconductor film and the ferroelectric polymer film. A high mobility of 6.5 cm² · V-1 · s-1 is achieved in the fabricated flexible Fe-OFET NVM, which also exhibits good memory performances with a large memory window of 17.2 V, a high memory on-off ratio up to 2 x 105, reliable switching endurance property over 600 cycles, and stable retention capability with the memory on-off ratio larger than 10² over 104 s, at the low programming/erasing voltages of ±15 V. [ABSTRACT FROM AUTHOR]

Abstract: We have developed stable and high performance etch‐stopper amorphous indium–gallium–zinc oxide thin‐film transistor (TFT) by using split active oxide semiconductor. The amorphous indium–gallium–zinc oxide TFTs exhibit the mobility as high as over 70 cm2/Vs and the stable operation under positive bias temperature stress. In this work, we demonstrated a 4‐in. transparent active‐matrix organic light‐emitting diode display using oxide TFT backplane with split active layer, where the gate driver is integrated. [ABSTRACT FROM AUTHOR]