Large-Area Growth of Ferroelectric 2D γ-In2 Se3 Semiconductor by Spray Pyrolysis for Next-Generation Memory

In2 Se3 , 2D ferroelectric-semiconductor, is a promising candidate for next-generation memory device because of its outstanding electrical properties. However, the large-area manufacturing of In2 Se3 is still a big challenge. In this work, spray pyrolysis technique is introduced for the growth of large-area In2 Se3 thin film. A polycrystalline γ-In2 Se3 layer can be grown on 15 cm × 15 cm glasss at the substrate temperature of 275 °C. The In2 Se3 ferroelectric-semiconductor field effect transistor (FeS-FET) on glass substrate demonstrates a large hysteresis window of 40.3 V at the ±40 V of gate voltage sweep and excellent uniformity. The FeS-FET exhibits an electron field effect mobility of 0.97 cm2 V-1 s-1 and an on/off current ratio of >107 in the transfer curves. The memory behavior of the large-area, In2 Se3 FeS-FETs for next-generation memory is demonstrated.

Influence of NF3 Plasma-Treated HfO2 Gate Insulator Surface on Tin Oxide Thin-Film Transistors

We studied the impact of NF3 plasma treatment on the HfO2 gate insulator of amorphous tin oxide (a-SnOx) thin-film transistors (TFTs). The plasma treatment was for 0, 10, or 30 s. The HfO2 insulator demonstrated a slightly higher breakdown voltage, whereas the capacitance value remained almost constant (~150 nF/cm2). The linear mobility slightly increased from ~30 to ~35 cm2/Vs when the treatment time increased from 0 to 10 s, whereas a 30 s-treated TFT demonstrated a decreased mobility of ~15 cm2/Vs. The subthreshold swing and the threshold voltage remained in the 100-120 mV/dec. range and near 0 V, respectively. The hysteresis dramatically decreased from ~0.5 V to 0 V when a 10 s treatment was applied, and the 10 s-treated TFT demonstrated the best stability under high current stress (HCS) of 100 μA. The analysis of the tin oxide thin film crystallinity and oxygen environment demonstrated that the a-SnOx remained amorphous, whereas more metal-oxygen bonds were formed with a 10 s NF3 plasma treatment. We also demonstrate that the density of states (DOS) significantly decreased in the 10 s-treated TFT compared to the other conditions. The stability under HCS was attributed to the HfO2/a-SnOx interface quality.

Second Data Release from the European Pulsar Timing Array: Challenging the Ultralight Dark Matter Paradigm

Pulsar Timing Array experiments probe the presence of possible scalar or pseudoscalar ultralight dark matter particles through decade-long timing of an ensemble of galactic millisecond radio pulsars. With the second data release of the European Pulsar Timing Array, we focus on the most robust scenario, in which dark matter interacts only gravitationally with ordinary baryonic matter. Our results show that ultralight particles with masses 10^{-24.0}  eV≲m≲10^{-23.3}  eV cannot constitute 100% of the measured local dark matter density, but can have at most local density ρ≲0.3  GeV/cm^{3}.

Multifunctional Crystalline InGaSnO Phototransistor Exhibiting Photosensing and Photosynaptic Behavior Using Oxygen Vacancy Engineering

A multifunctional optoelectronic device implementing photodetector, photosynapse, and photomemory is of increasing attention for neuromorphic system. This enables multiple devices to be replaced with a single device, which simplifies the structure of complex, highly integrated electronics. Here, a multifunctional c-axis-aligned crystalline indium gallium tin oxide thin-film transistor (TFT) optoelectronic device is demonstrated. The photodetecting and photosynaptic behaviors could be demonstrated by tuning of gate pulse. The device shows a high responsivity of 1.1 × 106  A W-1 to blue light (467 nm) and cutoff frequency (f-3dB ) of 2400 Hz exhibiting high frequency switching using a gate reset pulse. It is possible to implement photosynaptic behavior using persistent photoconductivity effect by applying a gate bias to make the TFT depletion mode. When potentiation and depression of synaptic weight are implemented with light pulse and gate voltage pulse, respectively, 64-state potentiation-depression curves are demonstrated with excellent nonlinearity of 1.13 and 2.03, respectively. When an artificial neural network is constructed with this device for the Modified National Institute of Standards and Technology training pattern recognition simulation, it shows a high pattern recognition accuracy of 90.4%.

Low-Temperature Solution-Processed HfZrO Gate Insulator for High-Performance of Flexible LaZnO Thin-Film Transistor

Metal-oxide-semiconductor (MOS)-based thin-film transistors (TFTs) are gaining significant attention in the field of flexible electronics due to their desirable electrical properties, such as high field-effect mobility (μFE), lower IOFF, and excellent stability under bias stress. TFTs have widespread applications, such as printed electronics, flexible displays, smart cards, image sensors, virtual reality (VR) and augmented reality (AR), and the Internet of Things (IoT) devices. In this study, we approach using a low-temperature solution-processed hafnium zirconium oxide (HfZrOx) gate insulator (GI) to improve the performance of lanthanum zinc oxide (LaZnO) TFTs. For the optimization of HfZrO GI, HfZrO films were annealed at 200, 250, and 300 °C. The optimized HfZrO-250 °C GI-based LaZnO TFT shows the μFE of 19.06 cm2V-1s-1, threshold voltage (VTH) of 1.98 V, hysteresis voltage (VH) of 0 V, subthreshold swing (SS) of 256 mV/dec, and ION/IOFF of ~108. The flexible LaZnO TFT with HfZrO-250 °C GI exhibits negligible ΔVTH of 0.25 V under positive-bias-temperature stress (PBTS). The flexible hysteresis-free LaZnO TFTs with HfZrO-250 °C can be widely used for flexible electronics. These enhancements were attributed to the smooth surface morphology and reduced defect density achieved with the HfZrO gate insulator. Therefore, the HfZrO/LaZnO approach holds great promise for next-generation MOS TFTs for flexible electronics.

As-Grown Crystalline InGaZnO by Spray Pyrolysis on a Flexible Substrate for a Thin-Film Transistor with Excellent Stability

The development of low-cost, high-mobility oxide thin-film transistors (TFTs) with excellent stability is of increasing interest. The coplanar oxide TFTs can be used for high-speed, large-area, and high-resolution displays. Here, we report highly oriented, as-grown crystalline InGaZnO (c-IGZO) with very low oxygen vacancy defects using spray pyrolysis at the substrate temperature of 425 °C. The c-IGZO exhibits a highly oriented, c-axis aligned crystal perpendicular to the substrate with a high mass density of 6.73 g cm-3 without any disordered incubation layer. Its resistivity can be decreased to 0.42 mΩ cm by NF3 plasma doping, which is essential to achieving high-performance coplanar TFT. We have demonstrated the application of this material to high-performance flexible TFTs. The self-aligned, coplanar c-IGZO TFTs on the polyimide substrate exhibit an average field-effect mobility of 39.60 cm2 V-1 s-1, threshold voltage of -1.00 V, subthreshold swing of 0.21 V dec-1, and on/off current ratio over 108. The ring oscillator and gate driver made of the c-IGZO TFTs exhibit a propagation delay of 8.77 ns/stage and rising/falling times of 648/564 ns, respectively. Therefore, the as-grown c-IGZO by spray pyrolysis has the potential to be utilized as a new oxide semiconductor for the production of low-cost, flexible TFT electronics.

Retraction: High‐Efficiency, Blue, Green, and Near‐Infrared Light‐Emitting Diodes Based on Triple Cation Perovskite

Adv. Optical Mater. 2017, 5, 1600920

https://doi.org/10.1002/adom.201600920

The above article, published online on 2 February 2017 in Wiley Online Library (https://doi.org/10.1002/adom.201600920), has been retracted by agreement between the authors, the journal's Editor‐in‐Chief, Anja Wecker, and Wiley‐VCH GmbH. An initial concern on atypical noise patterns in Figure 3 and Figure S1 was raised by third parties. An expert analysis of the requested raw data has revealed clear signatures of data manipulation. As a result, the conclusions of this study are considered not reliable.

Anticoagulant treatment patterns and thromboembolic events by tumor type among patients with VTE and cancer

Background

Patients with venous thromboembolism (VTE) and cancer are at higher risk of adverse outcomes (mortality, recurrent VTE etc.) versus patients with cancer alone; as such, clinical guidelines recommend anticoagulant treatment for patients with VTE and cancer. There is limited real world data about how anticoagulant treatment and thromboembolic outcomes differ by tumor type in patients with VTE and cancer. Understanding such differences may help identify appropriate anticoagulant treatment for specific tumor types.

Purpose

To describe anticoagulant treatment patterns and thromboembolic outcomes by tumor type among patients with VTE and cancer.

Methods

Patients with VTE and cancer age ≥65 were identified from the Surveillance, Epidemiology and End Results (SEER) Medicare database from 1/1/2014–12/31/2019. Patients were required to be enrolled for ≥6-months prior to their first VTE diagnosis (index) and without evidence of other conditions requiring anticoagulant (i.e., atrial fibrillation) prior to index. Cancer status and tumor type were identified from SEER or Medicare database in the 6-months prior through 30-days post VTE. This analysis focused on the following specific tumor types: high risk (brain, pancreas, and stomach) and common tumor types (breast, and prostate). Patients treated with an anticoagulant within 30-days after index were included in the final population. Major bleeding (MB) and recurrent VTE events were measured during follow-up (index date through earliest of disenrollment, death or 12/31/2019).

Results

A total of 3,546 anticoagulated patients with VTE and cancer of interest met all study criteria (breast [n=1,197], prostate [n=849], pancreatic [n=995], brain [n=248] and stomach [n=257] cancer). Patient mean age ranged from 73 (brain) to 76 (stomach) at index. Anticoagulant treatment patterns varied by tumor type (Figure 1). LMWH was more likely to be used in the 3 high risk tumor types whereas apixaban and rivaroxaban were more likely to be used in the 2 common tumor types. The incidence rate of recurrent VTE and major bleeding events also varied among different tumor types: ranging from 1.4 (breast) to 6.4 (pancreatic) per 100 person-years for recurrent VTE and from 4.3 (prostate) to 15.1 (pancreatic) per 100 person-years for major bleeding (Figure 2).

Conclusion

There are notable variations in anticoagulant treatment patters and the risks of major bleeding and recurrent VTE events by tumor type among patients with VTE and cancer. Further research is needed to understand which anticoagulant treatment option is more appropriate for VTE patients with specific tumor type.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Pfizer Inc. and Bristol Myers Squibb Company

Photonic nanostructures mimicking floral epidermis for perovskite solar cells

Here, we report photonic nanostructures replicated from the adaxial epidermis of flower petals onto light-polymerized coatings using low-cost nanoimprint lithography at ambient temperature. These multifunctional nanocoatings are applied to confer enhanced light trapping, water repellence, and UV light and environmental moisture protection features in perovskite solar cells. The former feature helps attain a maximum power conversion efficiency of 24.61% (21.01% for the reference cell) without any additional device optimization. Added to these merits, the nanocoatings also enable stable operation under AM 1.5G and UV light continuous illumination or in real-world conditions. Our engineering approach provides a simple way to produce multifunctional nanocoatings optimized by nature's wisdom.

Nano-Scale Ga2O3 Interface Engineering for High-Performance of ZnO-Based Thin-Film Transistors

Thin-film transistor (TFT) is a essential device for future electronics driving the next level of digital transformation. The development of metal-oxide-semiconductor (MOS) TFTs is considered one of the most advantageous devices for next-generation, large-area flexible electronics. This study demonstrates the systematic study of the amorphous gallium oxide (a-Ga₂O₃) and its application to nanocrystalline ZnO TFTs. The TFT with a-Ga₂O₃/c-ZnO-stack channel exhibits a field-effect mobility of ∼41 cm² V^-1 s^-1 and excellent stability under positive-bias-temperature stress. The a-Ga₂O₃/c-ZnO-stack TFT on polyimide (PI) substrate exhibits a negligible threshold voltage shift upon 100k bending cycles with a radius of 3 mm and is very stable under environmental test. The smooth morphology with tiny grains of ∼12 nm diameter with fewer grain boundary states improves the charge transport in Ga₂O₃/ZnO-stack TFT. The existence of amorphous a-Ga₂O₃ in between very thin ZnO layers helps to enhance the heterointerfaces and reduce the defect density in Ga₂O₃/ZnO interface. Therefore, integrating a-Ga₂O₃ in the ZnO channel in stacked TFT can increase mobility and enhance stability for next-generation flexible TFT electronics.

Polycrystalline InGaO Thin-Film Transistors with Coplanar Structure Exhibiting Average Mobility of ≈78 cm2 V-1 s-1 and Excellent Stability for Replacing Current Poly-Si Thin-Film Transistors for Organic Light-Emitting Diode Displays

Highly ordered polycrystalline indium gallium oxide (PC-IGO) film is obtained by the crystallization of room temperature sputtered amorphous IGO on a hot plate at 350 °C for 1 h and then annealed for 1 h in an N₂ O environment. A high-density PC-IGO of ≈7.15 g cm^-3 with reduced oxygen vacancy (≈14.83%) and hydroxyl (OH) related defects (≈10.96%) has been obtained by N₂ O annealing. Self-aligned coplanar thin-film transistor (TFT) with the PC-IGO exhibits the average saturation mobility of 78.73 cm² V^-1 s^-1 , threshold voltage of -1.07 V, subthreshold swing of 0.147 V dec^-1 , and the on/off current ratio of over 10⁸ . The TFTs show excellent stability under bias-temperature stress with a negligible threshold voltage shift (ΔV_TH ) of + 0.1 and -0.1 V for the positive and negative bias stresses, respectively. The TFTs exhibit very stable environmental stability when the TFTs are stored under high humidity (85%) and a high temperature (85 °C) for 2 days. The ring oscillator and the gate driver mode of the PC-IGO TFTs exhibit the propagation delay of 7.44 ns/stage with rising/falling times of less than 0.7 μs, respectively. Therefore, the PC-IGO TFTs are suitable for large area, high-resolution active-matrix organic, and inorganic light-emitting diodes displays.

Highly Sensitive, Stretchable Pressure Sensor Using Blue Laser Annealed CNTs

A piezoresistive sensor is an essential component of wearable electronics that can detect resistance changes when pressure is applied. In general, microstructures of sensing layers have been adopted as an effective approach to enhance piezoresistive performance. However, the mold-casted microstructures typically have quite a thick layer with dozens of microscales. In this paper, a carbon microstructure is formed by blue laser annealing (BLA) on a carbon nanotube (CNT) layer, which changes the surface morphology of CNTs into carbonaceous protrusions and increases its thickness more than four times compared to the as-deposited layer. Then, the pressure sensor is fabricated using a spin-coating of styrene–ethylene–butylene–styrene (SEBS) elastomer on the BLA CNTs layer. A 1.32 µm-thick pressure sensor exhibits a high sensitivity of 6.87 × 105 kPa−1, a wide sensing range of 278 Pa~40 kPa and a fast response/recovery time of 20 ms, respectively. The stability of the pressure sensor is demonstrated by the repeated loading and unloading of 20 kPa for 4000 cycles. The stretchable pressure sensor was also demonstrated using lateral CNT electrodes on SEBS surface, exhibiting stable pressure performance, with up to 20% stretching.

Volumetric Measurement of Relative CBV Using T1-Perfusion-Weighted MRI with High Temporal Resolution Compared with Traditional T2*-Perfusion-Weighted MRI in Postoperative Patients with High-Grade Gliomas

BACKGROUND AND PURPOSE

T1-PWI with high temporal resolution may provide a reliable relative CBV value as a valid alternative to T2*-PWI under increased susceptibility. The purpose of this study was to assess the technical and clinical performance of T1-relative CBV in patients with postoperative high-grade gliomas.

MATERIALS AND METHODS

Forty-five MRIs of 34 patients with proved high-grade gliomas were included. In all MRIs, T1- and T2*-PWIs were both acquired and processed semiautomatically to generate relative CBV maps using a released commercial software. Lesion masks were overlaid on the relative CBV maps, followed by a histogram of the whole VOI. The intraclass correlation coefficient and Bland-Altman plots were used for quantitative and qualitative comparisons. Signal loss from both methods was compared using the Wilcoxon signed-rank test of zero voxel percentage. The MRIs were divided into a progression group (n = 20) and a nonprogression group (n = 14) for receiver operating characteristic curve analysis.

RESULTS

Fair intertechnique consistency was observed between the 90th percentiles of the T1- and T2*-relative CBV values (intraclass correlation coefficient = 0.558, P < .001). T2*-PWI revealed a significantly higher percentage of near-zero voxels than T1-PWI (17.7% versus 3.1%, P < .001). There was no statistically significant difference between the area under the curve of T1- and T2*-relative CBV (0.811 versus 0.793, P = .835). T1-relative CBV showed 100% sensitivity and 57.1% specificity for the detection of progressive lesions.

CONCLUSIONS

T1-relative CBV demonstrated exquisite diagnostic performance for detecting progressive lesions in postoperative patients with high-grade gliomas, suggesting the potential role of T1-PWI as a valid alternative to the traditional T2*-PWI.

Attenuation of intrinsic aging of the skin via elimination of senescent dermal fibroblasts with senolytic drugs

BACKGROUND

Skin aging is caused by numerous factors that result in structural and functional changes in cutaneous components. Research has shown that senescent cells are known to accumulate in skin aging, however, the role of senescent cells in skin aging has not been defined.

OBJECTIVES

To elucidate the role of senescent cell in skin aging, we evaluated the effect of known senolytic drugs on senescent dermal fibroblasts.

METHODS

Primary human dermal fibroblasts (HDFs) were induced to senescence by long-term passaging, UV irradiation, and H2O2 treatment. Cell viability was measured after treatment of ABT-263 and ABT-737 on HDFs. Young and aged hairless mice were intradermally injected with drugs or vehicle on the dorsal skin for 10 days. Skin specimens were obtained and reverse-transcription quantitative PCR, western blotting, and histological analysis were performed.

RESULTS

We found that ABT-263 and ABT-737 induced selective clearance of senescent dermal fibroblasts, regardless of the method of senescence induction. Aged mouse skin treated with ABT-263 or ABT-737 showed increased collagen density, epidermal thickness, and proliferation of keratinocytes, as well as decreased senescence-associated secretory phenotypes, such as MMP-1 and IL-6.

CONCLUSIONS

Taken together, our results indicate that selective clearance of senescent skin cells can attenuate and improve skin aging phenotypes and that senolytic drugs may be of potential use as new therapeutic agents for treating aging of the skin.

Gel-based precursors for the high-performance of n-channel GaInSnZnO and p-channel CuGaSnSO thin-film transistors

The performance of metal-oxide thin-film transistors (TFTs) should be further improved for the applications of next-generation displays. Here, the developments of gel-derived gallium-indium-tin-zinc oxide (GITZO) for n-channel and copper-gallium-tin-sulfide oxide (CGTSO) for p-channel TFTs are demonstrated. The a-GITZO film by gel-based precursor gives an excellent interface with ZrO _x compared to the GITZO deposited using pristine or purified precursor. The gel-derived GITZO TFT exhibits the saturation mobility (μ _sat) of 28.6 ± 2.15 cm² V^-1 s^-1, three-fold higher than the pristine one, and excellent bias stability. The boost in GITZO TFT performances is due to the purity of the metal oxide material and higher film density with smooth surface morphology. In addition, the field-effect mobility (μ _FE) of the p-channel copper-tin-sulfide-gallium oxide (CGTSO) TFT could be increased from 1.71 to 4.25 cm² V^-1 s^-1 using a gel-derived precursor solution. Therefore, these results demonstrate that the gel-derived metal-oxide precursor by the solution process is a promising one for the high performance of the TFT backplane.

Intraindividual Comparison between the Contrast-Enhanced Golden-Angle Radial Sparse Parallel Sequence and the Conventional Fat-Suppressed Contrast-Enhanced T1-Weighted Spin-Echo Sequence for Head and Neck MRI

BACKGROUND AND PURPOSE

The golden-angle radial sparse parallel-volumetric interpolated breath-hold (GRASP-VIBE) sequence is a recently introduced imaging technique with high resolution. This study compared the image quality between conventional fat-suppressed T1-weighted TSE and GRASP-VIBE after gadolinium enhancement in the head and neck region.

MATERIALS AND METHODS

Data from 65 patients with clinical indications for head and neck MR imaging between September 2020 and January 2021 were retrospectively reviewed. Two radiologists assessed the overall image quality, overall artifacts, and image conspicuities in the oropharynx, hypopharynx, and cervical lymph nodes according to 5-point scores (best score: 5). Interobserver agreement was assessed using weighted κ statistics. The SNR and contrast-to-noise ratio were calculated and compared between the 2 sequences using a paired Wilcoxon signed rank test.

RESULTS

The analysis included 52 patients (mean age, 60 [SD, 14 ] years; male, 71.2% [37/52]) who were mostly diagnosed with head and neck malignancies (94.3% [50/52]). κ statistics ranged from slight agreement in cervical lymph node conspicuity (κ = 0.18) to substantial agreement in oropharyngeal mucosal conspicuity (κ = 0.80) (κ range, 0.18-0.80). Moreover, GRASP-VIBE demonstrated significantly higher mean scores in overall image quality (4.68 [SD, 0.41] versus 3.66 [SD, 0.73]), artifacts (4.47 [SD, 0.48] versus 3.58 [SD, 0.71]), oropharyngeal mucosal conspicuity (4.85 [SD, 0.41] versus 4.11 [SD, 0.79]), hypopharyngeal mucosal conspicuity (4.84 [SD, 0.34] versus 3.58 [SD, 0.81]), and cervical lymph node conspicuity (4.79 [SD, 0.32] versus 4.08 [SD, 0.64]) than fat-suppressed T1-weighted TSE (all, P < .001). Furthermore, GRASP-VIBE demonstrated a higher SNR (22.8 [SD, 11.5] versus 11.3 [SD, 5.6], P < .001) and contrast-to-noise ratio (4.7 [SD, 5.4] versus 2.3 [SD, 2.7], P = .059) than fat-suppressed T1-weighted TSE.

CONCLUSIONS

GRASP-VIBE provided better image quality with fewer artifacts than conventional fat-suppressed T1-weighted TSE for the head and neck regions.