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The development of high mobility emissive organic semiconductors is significant for advancing optoelectronic devices with simplified architecture and enhanced performance. The herringbone‐packed structure is regarded as the ideal arrangement for simultaneously achieving high mobility and strong emission in organic semiconductors. However, it remains a great challenge that the relationship between molecular structure and optoelectronic property is still elusive. Herein, four quinoline‐substituted anthracene isomers were designed and synthesized by introducing quinoline groups to anthracene core. Their intermolecular interactions and packing mode in the herringbone‐packed structures were regularly tuning by subtle changing the nitrogen position on quinoline group, resulting in the superior integration of optoelectronic properties. Through a comprehensive analysis of aggregation states and optoelectronic properties, we revealed that in herringbone‐packed aggregates, a centroid distance of approximately 7–7.5 Å along CH‐π direction and 6–6.5 Å along π–π direction is beneficial for simultaneously achieving high mobility and strong emission. These properties are closely related to the molecular twist angles, which are influenced by intramolecular interactions. This structure–property relationship has been further validated in other herringbone‐packed high mobility emissive organic semiconductors, demonstrating its broad applicability and universal potential. This work figures out the practical molecular design principle for high mobility emissive organic semiconductors. [ABSTRACT FROM AUTHOR]

High‐mobility emissive n‐type polymer semiconductors (HMEN‐CPs) are essential for organic optoelectronic devices. However, due to the lack of highly electron‐deficient building blocks with excellent physicochemical properties and the molecular design trade‐offs, the development of HMEN‐CPs has significantly lagged behind that of p‐type counterparts. Here, a new electron‐deficient acceptor, TFBVDPP is developed, by integrating the efficient carrier‐transporting diketopyrrolopyrrole and intense light‐emitting phenylene‐vinylene into a single molecule system. A series of all‐acceptor‐type polymers are synthesized by Pd‐catalyzed Suzuki polycondensation. The introduction of a vinyl bridge induces intra‐/intermolecular non‐covalent interactions, significantly narrowing the optical bandgap while enhancing coplanarity and crystallinity of the conjugated backbone, thus one of the polymers P1 exhibits ideal ambipolar transports with hole and electron mobilities reaching 4.6 and 3.7 cm2 V−1 s−1, respectively. Additionally, by directly homopolymerizing TFBVDPP, the non‐radiative transition is effectively suppressed, maintaining high electron transport while enhancing emission. This system shows excellent unipolar electron mobility (µe) and high quantum yield (Φ), achieving a record Φ · µe value exceeding 10−2 cm2 V−1 s−1, which is at least three orders of magnitude higher than the reported values. This study provides a new approach for developing HMEN‐CPs, and demonstrates their great potential in advancing organic optoelectronic technologies. [ABSTRACT FROM AUTHOR]

Active materials play a crucial role in the performance of phototransistors. However, the discovery of a novel and versatile active material is a big challenge. For the first time, phototransistors with ultrathin niobium‐doped indium oxide (InNbO) active layer are fabricated. The InNbO phototransistors without additional light‐absorbing layers exhibit the performance with a high average mobility of 22.86 cm2 V−1s−1, a turn‐on voltage of −0.75 V, a low sub threshold swing of 0.18 V/decade, and a high on/off current ratio of 5.74 × 108. Detailed studies show that Nb is the key to suppress the free carrier generation due to the strong bonding strength of Nb─O. In addition, the InNbO phototransistors exhibit a very broad spectral responsivity with a photocurrent of 4.72 × 10−4 A, a photosensitivity of 1.69 × 108, and a high detectivity of 3.33 × 1013 Jones under violet (405 nm) light illumination, which is significantly higher than that of the IGZO phototransistors. Furthermore, an active‐matrix quantum‐dot light‐emitting diode pixel circuit based on InNbO phototransistors is demonstrated. The findings not only indicate that InNbO is a new active material for phototransistors, but also suggest that InNbO‐based phototransistors have a great potential for the next‐generation interactive display technology. [ABSTRACT FROM AUTHOR]

In this paper, we propose a low‐complexity expectation propagation (EP) detector for orthogonal time frequency space (OTFS) system with practical rectangular waveforms. In the high‐mobility scenario, OTFS is becoming a potential scheme for the sixth‐generation (6G) wireless communication system. However, the large size of the effective delay‐Doppler (DD) domain channel matrix brings unbearable computational complexity to the signal detection algorithm based on the matrix inversion. We propose a low‐complexity EP detector based on the sparsity and the block circulant structure of the effective channel covariance matrix in the DD domain. The proposed algorithm only requires log‐linear complexity. In addition, simulation results show that the proposed algorithm not only has the advantage of low complexity but also has good performance, which achieves a tradeoff between performance and complexity. [ABSTRACT FROM AUTHOR]

Solution processing has emerged as a promising technique for the fabrication of oxide thin‐film transistors (TFTs), offering advantages such as low cost, high throughput, and exceptional compositional control. However, achieving reasonable electrical properties typically demands high annealing temperatures in the fabrication process. In addressing this challenge, a novel combination strategy is proposed that involves integrating the H2O2 inducement technique with infrared (IR) irradiation annealing. The study investigates the effects of precursors and IR irradiation annealing temperatures on the electrical properties of In2O3 TFTs. It is found that H2O2 can help accelerate the decomposition of organic residues, while IR irradiation annealing could enhance the film densification. By employing the proposed strategy, metal oxide TFTs consisting of a Zr‐Al‐O dielectric fabricated at 230 °C and an In2O3 channel layer fabricated at 185 °C demonstrated high performance with field‐effect mobility = 31.7 cm2 V−1·s−1, threshold voltage = 1.3 V, subthreshold swing = 0.13 V per decade, and on‐to‐off current ratio = 1.1 × 105. This work demonstrates the proposed combinational strategy is a general method to fabricate not only metal oxide semiconductors but also dielectrics. [ABSTRACT FROM AUTHOR]

The orthogonal time-frequency space (OTFS) technique is a promising method of waveform modulation that encodes data in the delay-doppler (DD) domain. OTFS distinguishes itself from conventional multiplexing methods by employing two-dimensional modulation to alternate between the time-frequency (TF) domain and the delay-Doppler domain. This feature enables the management of Doppler shifts induced by high-speed objects, which is not possible with conventional modulation schemes such as orthogonal frequency division multiplexing (OFDM). The main objective of this work is to provide a concise and comprehensive introduction of this emerging subject, emphasizing its system concept. In addition, we analyze crucial elements of OTFS modulation, including techniques for data detection, channel estimation, MIMO, and multiuser systems.

Granular flows, such as rockslide debris flows, can reach high velocities and travel vast distances, but mechanisms behind this high mobility remain elusive. Using the Discrete Element Method, we implement confined shear flow with fractal particle size distribution to study the physical mechanisms inside the highly localized basal zones. Our results show that the shear strength of confined flow decreases at large fractal dimensions, and a notable transition in shear behavior also occurs with increasing fractal dimension: large particles exhibit low granular temperature and act as solid phase within a semi‐diluted suspension, and small particles enter the rolling regime. The small particles behave as interstitial fluids and reduce the shear strength of confined flow. We suggest that the reduction of shear strength stemming from the fractal particle size distribution may provide insights into the mechanisms within the highly localized basal zones, ultimately contributing to the high mobility of granular flows. Plain Language Summary: Some geophysical flows are known for their high velocities and long travel distances. Many theories have been proposed to explain the long travel distances. There remains a puzzle among them, that is, whether the particle size distribution is one of the influencing factors. In this paper, we implement a series of confined shear flows to assess the effect of fractal particle size distribution on the shear behavior of the basal zone within granular flows. Our results show that, at a large fractal dimension, the large and small particles behave like solids and the fluid in suspension, respectively. Small particles with high angular velocity reduce the shear strength of the confined shear flows. We suggest that the reduction of shear strength might be one of the reasons for the long travel distances of some geophysical flows. Key Points: We demonstrate the relevance of two invariant quantities to the fractal dimension of confined shear flowWe show the suspension‐like transition of confined shear flow at a large fractal dimensionRolling regime of small particles results in "granular lubrication" phenomenon and reduces the shear strength of confined shear flow [ABSTRACT FROM AUTHOR]

A "high mobility scenario" involves individuals moving swiftly, such as on high-speed trains, airplanes, or congested urban automobiles. Channel estimation and data detection must be addressed as 6G wireless communication becomes more common and high-speed connectivity is needed for greater mobility. The existing works address high pilot overhead, inaccurate modeling, receiver complexity, low spatial resolution, and low signal-to-noise ratio. We propose a comprehensive solution using Zeros added Superimposed Sequence Pilot to enable reliable communication with low complexity equalization in MIMO-OTFS to overcome these issues. Sequentially transmitting pilot signals reduces pilot overhead, spectrum efficiency, and inter-user interference. Better receiver equalization. The equalizer minimizes inter-symbol, frequency domain, and DD domain inter-user interference for precise data identification. DOMP removes the drawbacks of the conventional OMP approach and produces more accurate channel estimates. Superimposed pilot signals reduce user and symbol interference. Arranging data, pilot, and guard symbols in the (DD) Domain reduces pilot overhead and interference. SNR, NMSE, QoS, BER, throughput, and latency are utilized to evaluate the proposed technique. [ABSTRACT FROM AUTHOR]

The top gate self‐alignment (TGSA) Praseodymium‐doped indium zinc oxide (PrIZO) thin film transistor (TFT) was fabricated with different process condition in our production line, and high field effect mobility of 40.83 cm2 V‐1 s‐1 was obtained by regulating the GI and ILD parameters. At the same time, the devices show excellent stability with PBTS of 0.52 V and NBTIS of ‐0.9 V, indicating its potential in overcoming the trade‐off between mobility and reliability. [ABSTRACT FROM AUTHOR]

A high mobility (29 cm2 /Vs) and high light stability oxide thin‐film transistor (TFT) with 8 mask back channel etched (BCE) structure has been fabricated. Remarkable enhancement in negative gate‐bias thermal stress with illumination has been achieved, resulting in a threshold voltage (Vth) shift of ‐0.01 V after 1 hour. A 16.0 inch WQHD 240Hz LCD NB has been developed using high mobility and high light stability oxide TFT in G8.5. [ABSTRACT FROM AUTHOR]

The present paper reports the study of electrical characteristics and bias temperature stress (BT) stability of crystalline Indium‐Gallium oxide (IGO) dual‐gate thin film transistor (TFT) with top‐gate structure. TFT with normalized Ion over 100εA and PBTS/NBTIS of 0.35/‐2.85V was successfully fabricated. By adjusting oxygen partial pressure (O2%) and substrate temperature, we can control the wet etching rate (WER) of as‐deposited IGO film. After post annealing, crystalline IGO containing In2O3 phase with preferred orientation of (222) has been formed. The TFT characteristics uniformity and BT stability were found to depend on parameters of gate insulator (GI) deposition and pre‐treatment before GI. Based on experimental results, we propose high GI deposition temperature associated with low N2O plasma treatment power as the optimal condition for industrial production of crystalline IGO TFT. [ABSTRACT FROM AUTHOR]

High‐end MNT, NBPC OLED displays require high resolution and high‐speed driving characteristics. In addition, as an OLED backplane, a high mobility and excellent reliability characteristics of TFT are required. We have developed high mobility devices by using Indium (In‐) rich a‐IGZO. In the In‐rich a‐IGZO TFT process, a relatively large amount of oxygen is used compared to conventional a‐IGZO (In:Ga:Zn 1:1:1) in order to control the variation of the threshold voltage (VTH) caused by high carrier concentration. However, the increase in excess oxygen leads to a decrease in reliability, making it even more difficult to satisfy both VTH dispersion and reliability at the same time. We have developed a‐IGZO TFTs that have excellent reliability characteristics while satisfying VTH dispersion and mobility by controlling the vertical and lateral distribution of oxygen and hydrogen. Furthermore, it has been confirmed that the 27‐inch QHD OLED monitor, which incorporates high‐mobility a‐IGZO TFTs, satisfies the product reliability characteristics. [ABSTRACT FROM AUTHOR]

The 13.2 inch AMOLED panel with 262 ppi has been fabricated with the high mobility metal oxide TFTs (thin film transistors). The high mobility oxide TFTs have high mobility ~34cm2 /Vs. On Gen. 6 glass, a small Vth variation with channel length 3.5um has been obtained. Moreover, the high mobility oxide TFT shows small Vth shift under positive/negative bias temperature stress (PBTS/NBTS). [ABSTRACT FROM AUTHOR]

The III-V/Ge complementary-FinFET (C-FinFET) based integrated circuits are more susceptible to radiation-induced single event transients (SET) than silicon counterparts. In this paper, the single event transients in n-channel InGaAs structures such as stacked 5-fin InGaAs-Bulk, InGaAs-Body on Insulator (InGaAs-BOI) and InGaAs-on-Insulator (InGaAs-OI) FinFETs are analyzed and optimized for SET-tolerant InGaAs/Ge-OI C-FinFET circuits. The SET analysis is done for these structures for different Linear Energy Transfer (LET), vertical strike positions, normal/angular strike incidences, gate underlap/overlap and oxide materials. The SET pulse widths for InGaAs/Ge-OI C-FinFETs are determined for different load capacitances, LETs, supply voltages and PMOS ON current. It is observed that the SET pulsewidth is lesser for InGaAs-OI/Ge-OI C-FinFETs compared to other two chosen structures. However, having the advantages of both InGaAs-Bulk and InGaAs-OI structures, the InGaAs-BOI FinFET with lesser pulsewidth than InGaAs-Bulk FinFET is a better candidate to use in radiation-prone environment. [ABSTRACT FROM AUTHOR]

High‐performance thin film transistors with a remarkable mobility of 38.7 cm2/Vs and excellent stability are demonstrated using amorphous indium zinc oxide (IZO)/indium gallium zinc oxide (IGZO) bilayer film as the active layer. The optimal performance of the bilayer device is found to be contingent upon the critical balance of oxygen flow ratio during sputtering IZO film. The mechanism governing the oxygen‐tuned performance has been thoroughly investigated. A 31‐inch ink‐jet printed AMOLED display panel has been successfully fabricated, with the GOA circuit integrated using this high mobility transistors. The good display performance showcases the significant application potential of the IZO/IGZO bilayer device. [ABSTRACT FROM AUTHOR]

Abstract Granular flows, such as rockslide debris flows, can reach high velocities and travel vast distances, but mechanisms behind this high mobility remain elusive. Using the Discrete Element Method, we implement confined shear flow with fractal particle size distribution to study the physical mechanisms inside the highly localized basal zones. Our results show that the shear strength of confined flow decreases at large fractal dimensions, and a notable transition in shear behavior also occurs with increasing fractal dimension: large particles exhibit low granular temperature and act as solid phase within a semi‐diluted suspension, and small particles enter the rolling regime. The small particles behave as interstitial fluids and reduce the shear strength of confined flow. We suggest that the reduction of shear strength stemming from the fractal particle size distribution may provide insights into the mechanisms within the highly localized basal zones, ultimately contributing to the high mobility of granular flows.

Fifth-generation(5G) and beyond communication systems, assisted by Intelligent Reflecting Surfaces (IRS), often encounter hindrances such as unreliable connections, high energy usage, and prolonged latency. Channel estimation in IRS-aided systems is challenging in vehicular communication systems with roadside IRS units and fast-moving users. This paper proposes an efficient and low-complex channel estimation strategy for high-speed vehicular mmWave communication systems equipped with roadside IRS. The method consists of two stages, sensing and prediction, which aim to improve efficiency and accuracy under dynamic channel conditions. In the sensing phase, an initial assessment of channel characteristics is estimated by exploiting the sparse nature of the channel. We use the Compressive Sampling Matching Pursuit (CoSaMP) algorithm for accurate estimation with reduced computational complexity. The prediction stage consists of real-time tracking and prediction of the Angle of Arrival (AoA) and the Angle of Departure (AoD) using the Extended Kalman Filter (EKF). This ensures more accurate dynamic channel estimation based on predicted array response vectors without increasing the pilot overhead. Simulation results demonstrate that our proposed approach can offer precise channel estimation with significantly reduced training overhead.

Organic light‐emitting transistors (OLETs) are highly integrated and minimized optoelectronic devices with significant potential superiority in smart displays and optical communications. To realize these various applications, it is urgently needed for color‐tunable emission in OLETs, but remains a great challenge as a result of the difficulty for designing organic semiconductors simultaneously integrating high carrier mobility, strong solid‐state emission, and the ability for potential tunable colors. Herein, a high mobility emissive excimer organic semiconductor, 2,7‐di(2‐anthryl)‐9H‐fluorene (2,7‐DAF) was reasonably designed by introducing a rotatable carbon–carbon single bond connecting two anthracene groups at the 2,7‐sites of fluorene, and the small torsion angles simultaneously guarantee effective conjugation and suppress fluorescence quenching. Indeed, the unique stable dimer arrangement and herringbone packing mode of 2,7‐DAF single crystal enables its superior integrated optoelectronic properties with high carrier mobility of 2.16 cm2 ⋅ V−1 ⋅ s−1, and strong excimer emission with absolute photoluminescence quantum yield (PLQY) of 47.4 %. Furthermore, the voltage‐dependent electrically induced color‐tunable emission from orange to blue was also demonstrated for an individual 2,7‐DAF single crystal based OLETs for the first time. This work opens the door for a new class of high mobility emissive excimer organic semiconductors, and provides a good platform for the study of color‐tunable OLETs. [ABSTRACT FROM AUTHOR]

In this study, a simple and rapid method for the synthesis of molybdenum disulfide (MoS 2) through thermolysis was demonstrated. In the previous reported work, the thermolysis synthesis of MoS 2 usually required a two-step process. The process is time-consuming, and need high-temperature (900 °C). In this study, we synthesize large-area thin films quickly in a single step at 450 °C using both hydrogen gas and sulfur powders for synthesis and defect filling at the same time. The layer number of MoS 2 films, controlled by the precursor concentration, is determined to be between 3 and 10 layers via Raman spectroscopy and TEM analysis. XPS analysis revealed the optimal amount of sulfur powders for vacancy refilling, and films prepared with this amount exhibited high carrier mobility of up to 220 cm2/Vs. According to the author's knowledge, the carrier mobility of proposed samples is much higher than that of the reported data. [ABSTRACT FROM AUTHOR]

The development of high‐mobility neuromorphic transistors is essential to increase signal transmission speed and solve the von Neumann bottleneck issue. Herein, this work proposes cross‐linked Poly(4‐vinylphenol) (c‐PVP) as a dielectric layer to form an electric double layer (EDL), which plays a key role in synaptic transistors, and measure the ratio‐dependent characteristics of cross‐linking agents in c‐PVP. When the ratio of PVP to poly(melamine‐co‐formaldehyde) methylated (PMF) is 10:1, neuromorphic transistors is found to show the best performance with a memory window of 2.2 V and a mobility of 93.4 cm2 V−1 s−1. Fourier‐transform infrared spectroscopy (FT‐IR) results show that the reduction in the concentration of the cross‐linking agent generates more hydroxyl groups within the c‐PVP film. The 10:1 c‐PVP‐based synaptic device has an ultra‐low energy consumption of 15.8 pJ for a single pulse and a maximum paired pulse facilitation (PPF) index value of 291%. Additionally, synaptic characteristics, such as pulse duration time dependent plasticity, pulse intensity dependent plasticity, pulse rate dependent plasticity (SRDP), high band filtering, and short‐term memory (STM) conversion to long‐term memory (LTM), are also described and discussed. These results suggest that c‐PVP/ZnON‐based neuromorphic devices can be promising artificial synapses for memory and learning capabilities. [ABSTRACT FROM AUTHOR]

The design of novel acceptor molecular structures based on classical building blocks is regarded as one of the efficient ways to explore the application of organic conjugated materials in conductivity and electronics. Here, a novel acceptor moiety, thiophene-vinyl-diketopyrrolopyrrole (TVDPP), was envisioned and prepared with a longer conjugation length and a more rigid structure than thiophene-diketopyrrolopyrrole (TDPP). The brominated TVDPP can be sequentially bonded to trimethyltin-containing benzo[c][1,2,5]thiadiazole units via Suzuki polycondensation to efficiently prepare the polymer PTVDPP-BSz, which features high molecular weight and excellent thermal stability. The polymerization process takes only 24 h and eliminates the need for chlorinated organic solvents or toxic tin-based reagents. Density functional theory (DFT) simulations and film morphology analyses verify the planarity and high crystallinity of the material, respectively, which facilitates the achievement of high carrier mobility. Conductivity measurements of the polymeric material in the organic transistor device show a hole mobility of 0.34 cm2 V−1 s−1, which illustrates its potential for functionalized semiconductor applications. [ABSTRACT FROM AUTHOR]

The search of new high‐mobility two‐dimensional (2D) semiconductors is crucial for the development of next‐generation photodetectors, since current photodetectors based on single 2D semiconductors usually cannot simultaneously own ultrafast response rate and ultrahigh sensitivity. Here, using a facial method of sequentially oxidizing Bi2Se3 at optimal O content, a series of bismuth oxyselenide semiconductors (Bi3O2.5Se2, Bi2O2Se, Bi2SeO5) with appealing electronic applications are successfully synthesized. The crystal and band structures of a superlattice‐free Bi3O2.5Se2 phase are resolved by 3D electron diffraction and density functional theory calculations, showing a unique non‐neutral layered structure, moderate band gap, and small effective mass. More importantly, the concept of Bi2Se3 + O2 can be extended to synthesize the superlattice‐free Bi3O2.5Se2 ultrathin films by chemical vapor deposition, whose room‐temperature mobility can be as high as ≈150 cm2 V−1 s−1 based on Hall measurements. The ultrathin Bi3O2.5Se2 photodetectors with a simple device configuration simultaneously own ultrafast response time (≈31 µs), ultrahigh responsivity (≈8 × 104 A/W), and large detectivity (≈8 × 1013 Jones). This work not only introduces a facile way to regulate the phase in the bismuth oxyselenide family, but also provides an alternative candidate for ultrafast and ultrasensitive photodetectors. [ABSTRACT FROM AUTHOR]

The stacked structure thin film transistors (TFT) has caused the widespread attention to achieve high mobility and reliability simultaneously. To ensure the stacked structure TFT application to mass production, it is critical to reduce the number of mask‐count. In this paper, 8‐mask‐count stacked TFT‐array process using the first semiconductor layer overlapped with the source and drain layer directly, which is the first layer on the glass substrate, is studied. By adopting this novel process, the device mobility is 25.4 cm2/Vs, which is more than twice that of conventional top‐gate self‐aligned a‐IGZO device. Besides, the ΔVth under the positive bias stress of 30V and negative bias temperature illumination stress of ‐30V for 1 h is +0.41V and ‐0.13V, respectively, achieving the stability to the level of a‐IGZO TFTs. [ABSTRACT FROM AUTHOR]

Ln‐IZO based target was employed to deposit as a channel layer in amorphous Ln‐In‐Zn‐O thin‐film transistors. Here, we use the carrier/barrier bilayer stacked AOS TFTs to improve the mobility and stability. High mobility Ln‐oxide is for better charge transport. The barrier layer is fine‐tuned for better reliability. After optimization of the stacked structure of the active layer and the parameters of the PV SiO2 layer, the devices exhibited superior electric properties. The device shows high mobility (35.4 cm2/Vs) and small voltage shifts (1.1/‐1.5 V) of PBTS (positive bias temperature stress) and NBTIS (negative bias temperature illumination stress). We fabricated a 14 inch notebook liquid crystal display (LCD) with the Demux 1:3 circuit design using the high performance bilayer stacked TFTs. [ABSTRACT FROM AUTHOR]

To effectively enhance the mobility without other degradations, such as much negative threshold voltage, this work fabricated the a‐IGZO/a‐IZO heterojunction‐channel TFTs with dual‐gate structure. The fabricated a‐IZO/a‐IGZO with thicker a‐IGZO TFT shows high performance, including high mobility of 54.6 cm2 /Vs, small subthreshold swing of 0.26 V/dec, and good stability under PBTS and NBTIS. [ABSTRACT FROM AUTHOR]

In this paper, BLDA technology has been applied to realize the preparation of a LTPS TFT without ion implantation. The BLDA LTPS TFT gives the advantages of high mobility (~ 290.5 cm2/Vs), a smaller subthreshold voltage swing, kink‐free output curve, and excellent device stability under PBTS. The backplane technology has been successfully applied in 7.1‐inch Mini‐LED display products, and the lighting effect is uniform. This low‐cost technique is very suitable for the LTPS TFT backplane for large area, high resolution Mini/Micro LED displays. [ABSTRACT FROM AUTHOR]

Amorphous ITO TFT technology based on the anodization approach is demonstrated, featured with the source/drain electrodes and channel region made of one single ITO layer. The anodized ITO TFT fabricated at room temperature shows high performance, including high on/off current ratio up to 109, high mobility of 56.1 cm2 V‐1 s‐1, low subthreshold swing of 0.14 V/decade, near‐zero threshold voltage of 1.7 V and good stress stabilities. [ABSTRACT FROM AUTHOR]

Semiconductors processed at low temperature for complementary metal–oxide semiconductors (CMOS) devices are receiving considerable attention in the field of integrated electronic applications. In this work, we demonstrated a CMOS inverter constructed by n-type ZnON and p-type Te TFTs where all the processes have been done at low temperature. The electrical measurements of proposed TFTs exhibit high mobility (> 100 and > 3 cm2/Vs in case of ZnON and Te TFTs, respectively) and a stable on/off current ratio. The resulted CMOS inverter exhibits a high voltage swing and a high voltage gain of 15.89. Since all the synthesis and fabrication processes are performed at low temperatures with easy processing techniques, the results may open new opportunities in the field of integrated electronics field.

In this communication, we report a novel acceptor structural unit, TVDPP, that can be distinguished from classical materials based on TDPP structures. By designing a synthetic route via retrosynthetic analysis, we successfully prepared this monomer and further prepared polymer P2TVDPP with high yield using a Stille-coupling polymerization reaction. The polymer showed several expected properties, such as high molecular weight, thermal stability, full planarity, small π−π stacking distance, smooth interface, and so on. The absorption spectra and energy levels of the polymer were characterized via photochemical and electrochemical analysis. The organic field-effect transistor (OFET), which is based on P2TVDPP, exhibited excellent carrier mobility and an on/off current ratio of 0.41 cm2 V−1 s−1 and ~107, respectively, which is an important step in expanding the significance of DPP-based materials in the field of optoelectronic devices and organic electronics. [ABSTRACT FROM AUTHOR]

Abstract—5G cellular systems provide a new service called Ultra-Reliable Low-Latency Communications (URLLC). In many URLLC scenarios (e.g., intelligent transport systems), users move at high speed and transmit data in the uplink. The base station shall assign transmission parameters that satisfy the strict quality of service requirements of URLLC applications and consume the least amount of channel resources. At high speed, users often change the serving base station. In this case, the task of selecting transmission parameters is complicated by the fact that the base station does not have channel quality measurements for the new user. This paper proposes various methods for selecting the initial transmission parameters when user connects to the base station. Using simulations, the paper compares various methods for different user speeds. Recommendations are given on the selection of initial parameters that provide a low amount of consumed channel resources. [ABSTRACT FROM AUTHOR]

Conjugated polymer semiconductors based on donor–acceptor structures are commonly employed as core materials for optoelectronic devices in the field of organic electronics. In this study, we designed and synthesized a novel acceptor unit thiophene-vinyl-diketopyrrolopyrrole, named TVDPP, based on a four-step organic synthesis procedure. Stille coupling reactions were applied with high yields of polymerization of TVDPP with fluorinated thiophene (FT) monomer. The molecular weight and thermal stability of the polymers were tested and showed high molecular weight and good thermal stability. Theoretical simulation calculations and 2D grazing-incidence wide-angle X-ray scattering (GIWAXS) tests verified the planarity of the material and excellent stacking properties, which are favorable for achieving high carrier mobility. Measurements based on the polymer as an organic thin film transistor (OTFT) device were carried out, and the mobility and on/off current ratio reached 0.383 cm2 V−1 s−1 and 104, respectively, showing its great potential in organic optoelectronics. [ABSTRACT FROM AUTHOR]

Benzo[d][1,2,3]triazole (BTA) unit is one of the most classic electron‐accepting units (A) to construct donor (D)‐π‐A‐type photovoltaic polymers. However, the highest power conversion efficiency (PCE) of organic photovoltaics (OPVs) based on BTA‐containing polymers is restricted to 15–16%, lagging other promising polymers. Thus, investigating the structure‐performance relationship and breaking the efficiency bottleneck of BTA‐based polymers is challenging but critical. Herein, the effects of fusing two thiophene rings at D (PE52), π (PE4), and A (PE39) units of a classic D–π–A‐type BTA‐containing polymer J52‐Cl, respectively, on the backbone conformation, crystallinity, molecular stacking, and photovoltaic performance are systematically investigated. When blended with a BTA‐containing non‐fullerene acceptor (NFA), Y18, all three polymers with extending conjugated backbones can decrease the energy loss of photovoltaic devices. Notably, PE4, with a linear backbone conformation, realizes the champion PCE of 17.08%, with a short‐circuit current density (JSC) of 26.83 mA cm−2, a large breakthrough for BTA‐based photovoltaic polymers. What's more, the photovoltaic device based on PE4:Y18 combination fabricated by a non‐halogenated solvent of o‐xylene also displays an excellent PCE of 16.87%. The results indicate that fusing thiophene rings to BTA‐polymers, especially at π‐bridge, is a simple and effective method to improve the photovoltaic performance via modulating the molecular conformation and crystallinity. [ABSTRACT FROM AUTHOR]

Nowadays, high mobility scenarios have become increasingly common. The widespread adoption of High-speed Rail (HSR) in China exemplifies this trend, while more promising use cases, such as vehicle-to-everything, continue to emerge. However, the Internet access provided in high mobility environments still struggles to achieve seamless connectivity. The next generation of wireless cellular technology 5 G further poses more requirements on the end-to-end evolution to fully utilize its ultra-high band-width, while existing network diagnostic tools focus on above-IP layers or below-IP layers only. We then propose HiMoDiag, which enables flexible online analysis of the network performance in a cross-layer manner, i.e., from the top (application layer) to the bottom (physical layer). We believe HiMoDiag could greatly simplify the process of pinpointing the deficiencies of the Internet access delivery on HSR, lead to more timely optimization and ultimately help to improve the network performance.

Over the last few years, great advances have been achieved in exploration of high-mobility two-dimensional (2D) semiconductors such as metal chalcogenide InSe and noble-transition-metal dichalcogenide PdSe2. These materials are competitive candidates for constructing next-generation optoelectronic devices owing to their unique crystalline and electronic structures. Moreover, the optical and electronic properties of 2D materials can be efficiently modified via precisely engineering their band structures, which is critical for widening specific applications ranging from high-performance optoelectronics to catalysis and energy harvesting. In this review, we focus on the progress in bandgaps engineering of newly emerging high-mobility 2D semiconductors and their applications in optoelectronic devices, incorporating our recent study in the InSe and PdSe2 systems. First of all, we discuss the structure-property relationship of typical high-mobility 2D semiconductors (InSe and PdSe2). Next, we analyze several viable strategies for bandgap engineering, including thickness, strain or pressure, alloying, heterostructure, surface modification, intercalation, and so on. Furthermore, we summarize the optoelectronic devices fabricated with such high-mobility 2D semiconductors. The conclusion and outlook in this topic are finally presented. This review aims to provide valuable insights in bandgap engineering of newly emerging 2D semiconductors and explore their potential in future optoelectronic applications.

NdON, HfON, and their mixtures (NdxHf(1−x)ON) with different Hf contents are adopted as the gate dielectrics of pentacene organic thin‐film transistors (OTFTs). Their capacitance–voltage characteristics reveal that the Hf incorporation generates negative fixed charges in the dielectric for assisting the applied gate voltage, thus achieving a low threshold voltage for the OTFT. X‐ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) results indicate that Hf can suppress the hygroscopicity of Nd oxide while Nd can passivate the carrier traps (e.g., oxygen vacancies) of Hf oxide, both of which can contribute to a smoother dielectric surface for the growth of larger pentacene grains on the dielectric surface. As a result, among the samples with different Hf contents, the OTFT with Nd0.85Hf0.15ON can achieve the highest carrier mobility of 1.95 cm2 V−1 s−1 due to least Coulomb scattering (associated with lowest interface‐trap density of 5.9 × 1012 cm−2 eV−1 and smallest hysteresis of 0.26 V) and least grain‐boundary scattering (associated with largest pentacene grains). [ABSTRACT FROM AUTHOR]

Semiconductors processed at low temperature for complementary metal–oxide semiconductors (CMOS) devices are receiving considerable attention in the field of integrated electronic applications. In this work, we demonstrated a CMOS inverter constructed by n-type ZnON and p-type Te TFTs where all the processes have been done at low temperature. The electrical measurements of proposed TFTs exhibit high mobility (> 100 and > 3 cm2/Vs in case of ZnON and Te TFTs, respectively) and a stable on/off current ratio. The resulted CMOS inverter exhibits a high voltage swing and a high voltage gain of 15.89. Since all the synthesis and fabrication processes are performed at low temperatures with easy processing techniques, the results may open new opportunities in the field of integrated electronics field. [ABSTRACT FROM AUTHOR]

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Orthogonal time frequency space (OTFS) modulation is a booming multicarrier modulation technique and a promising candidate for achieving quality of services in high mobility scenarios of 5G new radio (NR) and beyond wireless communication systems. OTFS addresses the high Doppler channel environment aiding the 2D delay-Doppler (DD) domain rather than the conventional time frequency domain. OTFS exploits several 2D transformations to transform a temporally variant multipath channel into a nearly invariant DD. The information symbols are embedded and the channel is represented sparsely in the DD domain. OTFS combats the challenges like inter-symbol interference, inter-carrier interference, etc., and outperforms the orthogonal frequency division multiplexing scheme. This paper presents a detailed survey of various channel estimation (CE) and signal detection (SD) techniques with vital mathematical expressions adopted to achieve enhanced performance. The significant benefits, techniques aided, and challenges in CE and SD for OTFS to a wide range of applications in high mobility scenarios are also discussed. Moreover, the crucial lessons erudite from the review along with the future research directions and key challenges in integration of OTFS with recent technologies for achieving 6G benchmarks are conversed in this paper.

Recently, the two-dimensional (2D) fast Fourier transform (2D-FFT) filter bank (FB) technique was proposed as an alternative to new wireless communication technologies covering several application scenarios. This technique presents similar characteristics to orthogonal time-frequency space modulation (OTFS), such as lower PAPR and robustness in high mobility scenarios; in addition, thanks to the use of filter bank modulation, the technique has a good spectral localization. In this work, we present the generalization of the 2D-FFT FB system by making changes in the waveform structure to obtain advantages in the symbol detection process. The proposed idea allows the use of low-complexity equalizers in the time-frequency (TF) domain, bringing a good performance/complexity trade-off and obtaining bit error rate (BER) results of the same order than delay-Doppler domain receivers for OTFS. Theoretical and simulation results show that it is possible to obtain a good error performance in high mobility scenarios even using simple equalizers in the TF domain combined with waveform structure adjustments.

Fault detection is one of the basic components of fault-tolerant system,which can ensure the safe and reliable implementation of applications on vehicular ad hoc networks.However,vehicular ad hoc networks are different from traditional mobile ad hoc networks.On the one hand,vehicles have high-speed mobility and may join or leave the system at any time,which is likely to make the network environment to be changeable.On the other hand,the links between vehicles are often interrupted due to environmental and equipment factors,which is likely to cause message loss.In order to solve the above problems,a hierarchical fault detection method based on dead reckoning is proposed.In this fault detection method,the dead reckoning model is used to predict the transmission time of heartbeat messages,and the roadside unit is considered as a static node to build a hierarchical detection architecture,so as to improve the performance of fault detection in the vehicular ad hoc networks.Using the NS2 to build the si-mulation experimental platform for performance verification,experimental results show that the proposed fault detection method is better than the comparative fault detection method in terms of detection speed,detection accuracy and detection overhead.

Amorphous metal oxide semiconductor phototransistors (MOTPs) integrated with colloidal quantum dots (QDs) (QD‐MOTPs) are promising infrared photodetectors owing to their high photoconductive gain, low off‐current level, and high compatibility with pixel circuits. However, to date, the poor mobility of conventional MOTPs, such as indium gallium zinc oxide (IGZO), and the toxicity of lead (Pb)‐based QDs, such as lead sulfide and lead selenide, has limited the commercial applications of QD‐MOTPs. Herein, an ultrasensitive QD‐MOTP fabricated by integrating a high‐mobility zinc oxynitride (ZnON)–based MOTP and lead‐free indium arsenide (InAs) QDs is demonstrated. A new gradated bandgap structure is introduced in the InAs QD layer that absorbs infrared light, which prevents carriers from moving backward and effectively reduces electron–hole recombination. Chemical, optical, and structural analyses confirm the movement of the photoexcited carriers in the graded band structure. The novel QD‐MOTP exhibits an outstanding performance with a responsivity of 1.15 × 105 A W−1 and detectivity of 5.32 × 1016 Jones at a light power density of 2 µW cm−2 under illumination at 905 nm. [ABSTRACT FROM AUTHOR]

Two‐dimensional conjugated metal–organic frameworks (2D c‐MOFs) are emerging as a unique class of electronic materials. However, 2D c‐MOFs with band gaps in the Vis‐NIR and high charge carrier mobility are rare. Most of the reported conducting 2D c‐MOFs are metallic (i.e. gapless), which largely limits their use in logic devices. Herein, we design a phenanthrotriphenylene‐based, D2h‐symmetric π‐extended ligand (OHPTP), and synthesize the first rhombic 2D c‐MOF single crystals (Cu2(OHPTP)). The continuous rotation electron diffraction (cRED) analysis unveils the orthorhombic crystal structure at the atomic level with a unique slipped AA stacking. The Cu2(OHPTP) is a p‐type semiconductor with an indirect band gap of ≈0.50 eV and exhibits high electrical conductivity of 0.10 S cm−1 and high charge carrier mobility of ≈10.0 cm2 V−1 s−1. Theoretical calculations underline the predominant role of the out‐of‐plane charge transport in this semiquinone‐based 2D c‐MOF. [ABSTRACT FROM AUTHOR]

Zweidimensionale konjugierte metallorganische Gerüstverbindungen (2D c‐MOFs) gehören zu einer einzigartigen Gruppe elektronischer Materialien. 2D c‐MOFs mit Bandlücken im sichtbaren oder nahen IR‐Bereich und hohen Ladungsträger‐mobilitäten sind jedoch rar. Die meisten literaturbekannten halbleitenden 2D c‐MOFs sind metallisch, was ihre Verwendung in logischen Bauelementen stark einschränkt. Im Folgenden konzipieren wir einen Phenanthrotriphenylen basierten, D2h‐symmetrischen, π‐konjugierten Liganden (OHPTP) und synthetisieren die ersten rhombischen 2D c‐MOF Einkristalle (Cu2(OHPTP)). Kontinuierliche Rotations‐Elektronendiffraktometrie (cRED) belegt die orthorhombische Kristallstruktur mit versschobene AA‐Schichtung auf atomarer Ebene. Cu2(OHPTP) ist ein p‐Typ Halbleiter mit einer indirekten Bandlücke von ≈0.50 eV, einer hohen elektrischen Leitfähigkeit von 0.10 S cm−1 und einer hohen Ladungsträgermobilität von ≈10.0 cm2 V−1 s−1. Theoretische Berechnungen unterstreichen die dominierende Rolle des Ladungstransports zwischen den Schichten in diesem Semichinon verknüpften 2D c‐MOF. [ABSTRACT FROM AUTHOR]

This work reports the first nanocrystalline SnON (7.6% nitrogen content) nanosheet n-type Field-Effect Transistor (nFET) with the transistor's effective mobility (µeff) as high as 357 and 325 cm2/V-s at electron density (Qe) of 5 × 1012 cm−2 and an ultra-thin body thickness (Tbody) of 7 nm and 5 nm, respectively. At the same Tbody and Qe, these µeff values are significantly higher than those of single-crystalline Si, InGaAs, thin-body Si-on-Insulator (SOI), two-dimensional (2D) MoS2 and WS2. The new discovery of a slower µeff decay rate at high Qe than that of the SiO2/bulk-Si universal curve was found, owing to a one order of magnitude lower effective field (Eeff) by more than 10 times higher dielectric constant (κ) in the channel material, which keeps the electron wave-function away from the gate-oxide/semiconductor interface and lowers the gate-oxide surface scattering. In addition, the high µeff is also due to the overlapped large radius s-orbitals, low 0.29 mo effective mass (me*) and low polar optical phonon scattering. SnON nFETs with record-breaking µeff and quasi-2D thickness enable a potential monolithic three-dimensional (3D) integrated circuit (IC) and embedded memory for 3D biological brain-mimicking structures. [ABSTRACT FROM AUTHOR]

Compared to common asthma, obese asthma is difficult to control. Previous studies have shown that vitamin D (Vit D) has a therapeutic effect on asthma. Nevertheless, the action mechanism of Vit D for obese asthma are not well known. In this study, we, therefore, induced obesity and established an obese asthma mouse model using ovalbumin (OVA) stimulation and applied treatment with Vit D (100 ng/kg). Accordingly, thirty mice were randomly divided into 5 equal groups of normal control, asthma, obese asthma, asthma+Vit D, and obese asthma+ Vit D. The levels of inflammatory factors and adipokines were measured by the ELISA assay; then the quantitative reverse transcription PCR (qRT-PCR) method was used to evaluate the expression of high mobility group box 1(HMGB1) and receptor for advanced glycation end products [RAGE] genes. The results showed that OVA sensitization significantly increased airway resistance, the levels of inflammatory cytokines, and HMGB and RAGE expression in asthmatic and obese asthmatic mice, as compared to the control group. Also, these changes in the obese asthmatic group were notably higher than those in the asthmatic one. In addition, the treatment of asthmatic and obese asthmatic mice with Vit D significantly reduced the raw, serum and BALF levels of inflammatory cytokines, as well as the expression of HMGB1 and RAGE mRNA. To conclude, the present study showed that vitamin D might attenuate lung injury by upregulating HMGB1 and RAGE expression. Our findings, thus, may offer new concepts and approaches for the treatment and prevention of obese asthma. [ABSTRACT FROM AUTHOR]

We have developed a new oxide BCE technology with high mobility of more than 46 cm2/Vs and used it in a 13.3‐inch 144Hz oxide UHD LCD panel for a Notebook PC. Because of the low carrier concentration of the new oxide materials, the high mobility characteristics can be ensured by using single‐layer materials, and the homogeneity of the prepared short‐channel TFTs is also perfect. They also have reliability PBTS/NBTIS enough to use the application. These results indicate that a variety of backplanes are possible to be made in a single factory of Oxide. [ABSTRACT FROM AUTHOR]