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Background: Several studies to date have reported on the development of positron emission tomography (PET)/computed tomography (CT)-based models intended to effectively distinguish between benign and malignant pulmonary nodules (PNs). This meta-analysis was designed with the goal of clarifying the utility of these PET/CT-based conventional parameter models as diagnostic tools in the context of the differential diagnosis of PNs. Methods: Relevant studies published through September 2023 were identified by searching the Web of Science, PubMed, and Wanfang databases, after which Stata v 12.0 was used to conduct pooled analyses of the resultant data. Results: This meta-analysis included a total of 13 retrospective studies that analyzed 1,731 and 693 malignant and benign PNs, respectively. The respective pooled sensitivity, specificity, PLR, and NLR values for the PET/CT-based studies developed in these models were 88% (95%CI: 0.86–0.91), 78% (95%CI: 0.71–0.85), 4.10 (95%CI: 2.98–5.64), and 0.15 (95%CI: 0.12–0.19). Of these endpoints, the pooled analyses of model sensitivity (I2 = 69.25%), specificity (I2 = 78.44%), PLR (I2 = 71.42%), and NLR (I2 = 67.18%) were all subject to significant heterogeneity. The overall area under the curve value (AUC) value for these models was 0.91 (95%CI: 0.88–0.93). When differential diagnosis was instead performed based on PET results only, the corresponding pooled sensitivity, specificity, PLR, and NLR values were 92% (95%CI: 0.85–0.96), 51% (95%CI: 0.37–0.66), 1.89 (95%CI: 1.36–2.62), and 0.16 (95%CI: 0.07–0.35), with all four being subject to significant heterogeneity (I2 = 88.08%, 82.63%, 80.19%, and 86.38%). The AUC for these pooled analyses was 0.82 (95%CI: 0.79–0.85). Conclusions: These results suggest that PET/CT-based models may offer diagnostic performance superior to that of PET results alone when distinguishing between benign and malignant PNs. [ABSTRACT FROM AUTHOR]

Highlights • A unified explanation is proposed to consistently explain the two-step degradation of a-IGZO TFTs under DC PBTI stress without or with different stress V ds. • For PBTI stress without stress V ds , the initial negative V th shift is believed to be induced by donor-like defect states corresponding to H 2 O molecule and intrinsic defects. • For PBTI stress with stress V ds , the negative shift is believed to be induced by donor-like defect states corresponding to oxygen vacancies. The gate-bias-induced electron trapping mechanism is responsible for the positive V th shift. Abstract A unified explanation is proposed to consistently explain the two-step degradation of amorphous InGaZnO (a-IGZO) thin film transistors (TFTs) under DC positive bias temperature instability (PBTI) stress without or with different drain stress voltages (V ds). For PBTI stress without stress V ds , this initial negative V th shift is believed to be induced by donor-like defect states corresponding to H 2 O molecule and intrinsic defects, while for PBTI stress with stress V ds , the negative shift is believed to be induced by donor-like defect states corresponding to oxygen vacancies. The gate-bias-induced electron trapping mechanism is responsible for positive V th shift. These transitions from negative to positive V th shift are resulted from the competition between the donor-like states creation and electron trapping. [ABSTRACT FROM AUTHOR]

Mg-doped InZnO (MIZO) films were prepared by sol-gel method, and bottom-gate structured thin film transistors (TFTs) were prepared by using the MIZO films. Oxygen and argon (Ar) plasma treatments were carried out on the film and TFTs. The X-ray photoelectron spectroscopy (XPS) results show that both Ar and oxygen etching can increase the oxygen deficiencies, which effectively increase the content of carrier concentration in MIZO films. After both kinds of plasma treatment, the field effect mobility of the MIZO TFTs is greatly improved and the on/off current ratio increases two orders of magnitude. [ABSTRACT FROM AUTHOR]

• Positive charges from H 2 O molecule induced the parasitic current path, resulting in anomalous hump in subthreshold region at elevated temperature, which disappeared after N 2 annealing. • Hump still existed under PBS, while weakened hump were observed under NBS due to positive charges trapping. In this work, we investigated an anomalous hump in the bottom-gate amorphous-InGaZnO thin-film transistors. The hump in the subthreshold region appeared at elevated temperature and disappeared after N 2 atmosphere annealing. The anomalous hump phenomenon is attributed to the existence of both main current path composed by electron and parasitic current path induced by positive charges formed by adsorbed H 2 O molecules. With the increase of the testing temperature, the hump effect becomes significant since the formation of positive charges is strengthened by heat. This hump can be weakened by negative bias temperature instability stress at high temperature due to the charge-trapping mechanism. [ABSTRACT FROM AUTHOR]

• A sharp interface can be obtained through Ni/Ti/Si reaction. • NiSi 2 is formed after 500 °C annealing through Ni/Ti reaction with 130 nm Si nanowires. • Fully silicided Ni-rich phases form in 15 and 25 nm nanowires. The morphology and phase transformation of nickel silicide nanowires with and without a titanium (Ti) interlayer have been studied. The Ni (10 nm) layers with or without 1 nm Ti film were sputtered onto the Si nanowires onto the silicon-on-insulator substrate and blanket Si wafers. Nickel silicide was formed by rapid thermal annealing at 500 °C in N 2 ambient. Ni 3 Si 2 forms in the 100–130 nm wide nickel silicide nanowire without a Ti interlayer, while the presence of a Ti layer results in epitaxial NiSi 2 formation. The Ti interlayer acts as a diffusion rate limiting barrier for Ni atoms, not only resulting in NiSi 2 formation, but also causing a smooth interface between the nickel silicide nanowire and the substrate. Fully silicided nanowire can be formed on narrow wires, where Ni is excess, leading to the formation of the Ni-rich phase, i.e., Ni 3 Si in the 15 nm nanowire for the Ni/Si reaction; and Ni 3 Si 2 in the 25 nm nanowire for the Ni/Ti/Si reaction. [ABSTRACT FROM AUTHOR]

In this work, an ultra-thin cobalt film is used as a passivation layer to achieve a Cu–Cu quasi-direct bonding process, and successful bonding was achieved at the bonding temperature of 230 °C with the bonding pressure of 0.5 MPa in non-vacuum conditions. A tensile bonding strength of over 12.8 MPa can be achieved. With the cobalt layer, the total film roughness is greatly reduced to around 1 nm, and the cross-sectional transmission electron microscope images reveal the presence of a void-free bonding interface. Time-of-flight secondary ion mass spectrometry depth analysis is carried out using a PVD deposited multilayer sample, which simulates the bonding process without pressure. It is found that a Cu–Co intermixing layer formed between the Cu and Co interfaces during annealing, and Cu has diffused into the Co layer. Due to the nanocrystalline structure of the Co film and the low roughness of the system, a low bonding temperature can be achieved. These results demonstrate that Co, which can be selectively grown on the Cu surface, can be used as a passivation layer to achieve low-cost and high-quality interconnect for the three-dimensional integrated circuits. [ABSTRACT FROM AUTHOR]

MoAlB is a ternary boride of MAB phases with strong resistance to oxidation and ablation at service temperature, thanks to preferential Al diffusion to form a protective oxide scale. However, excessive Al were often necessary in sintering of MoAlB ceramics, suggesting that a liquid-phase densification might occur thus leading to complex microstructures. By quantitative SEM analysis, ~17 mol.% Al 2 O 3 phase was found common in MoAlB ceramics. The liquid-phase of Al-Mo-B-O facilitates the direct conversion from MoB to MoAlB before in situ formation of Al 2 O 3. An intermediate Mo 3 Al 8 phase competes with layered conversion, which limits the insertion rate of Al into B-B layers of MoB to form abundant Al-deficient stacking-faults. Intermetallic Mo 3 Al 8 phase precipitates further in the intergranular regions parallel to the crystallization of Al 2 O 3 , leaving the reprecipitation of remaining Al. Both layered-conversion and intergranular oxides can improve ablation behavior for MoAlB ceramics, as well as fracture toughness and compressive strength. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Dense ZrB2–20vol% SiC ceramics (ZS) were fabricated by hot pressing using self-synthesized high purity ZrB2 and commercial SiC powders as raw materials. The high temperature flexural strength of ZS and its degradation mechanisms up to 1600°C in high purity argon were investigated. According to the fracture mode, crack origin and internal friction curve of ZS ceramics, its strength degradation above 1000°C is considered to result from a combination of phenomena such as grain boundary softening, grain sliding and the formation of cavitations and cracks around the SiC grains on the tensile side of the specimens. The ZS material at 1600°C remains 84% of its strength at room temperature, which is obviously higher than the values reported in literature. The benefit is mainly derived from the high purity of the ZrB2 powders. [Copyright &y& Elsevier]

Ultrafast High-temperature Sintering (UHS) has been successfully applied to fabricate the silicon nitride (Si 3 N 4) bulks, as the first attempt of ultra-rapid consolidation of a non-oxide ceramics. At a heating rate of 875 °C/min, the bulk Si 3 N 4 ceramic with a relative density greater than 96 % and an α-β phase transformation degree above 80 % could be obtained within 300 s. The effects of ultrafast heating on the liquid phase sintering (LPS) were also comparatively studied. Results showed that, the ultrafast heating rate and high temperature under UHS might promote the LPS system evolving to a nonequilibrium state. By comparing with other pressureless sintering processes with much lower heating rates, UHS apart from reducing the processing time, and it is also an effective method to form a bimodal microstructure composed of interlocked rod-like β-Si 3 N 4 grains. [ABSTRACT FROM AUTHOR]

High temperature flexural strength of ZrB2-20 vol% SiC ceramics ( ZS) up to 1600°C in high purity argon atmosphere was significantly improved by adding 5 vol% WC, but degraded when 5 vol% ZrC was added. ZrB2-20 SiC-5 WC ceramic ( ZSW) has a very high strength (mean ± SD) of 675 ± 33 MPa at 1600°C, and also an elastic and transgranular fracture mode was observed. According to the analysis of the fracture modes and crack origins in ZSW ceramics, the improvement in strength above 1000°C was attributed to the removal of the oxide impurities from grain boundaries. [ABSTRACT FROM AUTHOR]