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We have determined both the effective masses and the barrier heights for electrons and holes in pure SiO2 and lightly nitrided oxides with various nitrogen concentrations up to 4.5 at %. In contrast to previous studies which were usually carried out by assuming a value for either the effective mass or the barrier height, this study does not make such an assumption. The approach is proven to be reliable by examining the result for the well-studied pure SiO2 thin films. It is observed that with the increase of the nitrogen concentration the effective masses increase while both the barrier heights and the energy gap decrease. [ABSTRACT FROM AUTHOR]

By using double TiN x O y absorption layers with low N/O ratio (TiNO_L) and high N/O ratio (TiNO_H), a spectral selective solar absorber (SSA) with the structure of SiO 2 -TiO 2 -TiNO_L-TiNO_H-Cu has been proposed. Optical properties of the TiNO_L and TiNO_H layers are investigated with spectroscopic ellipsometry (SE) in the wavelength range of 0.3–2.5 μm using an optical dispersion model in which the absorption mechanisms in TiN x O y including the localized surface plasmon resonance (LSPR), free electron absorption and interband transitions are taken into account. Because TiNO_H has a higher free electron concentration than that of TiNO_L, the absorption due to both the LSPR and free electron absorption in TiNO_H is found larger than that in TiNO_L. With the model parameters of the dispersion model obtained from the SE modeling, the reflectance spectrum of the SSA in the wide wavelength range of 0.3–25 μm covering both the solar radiation and heat radiation of a hot surface has been simulated; and the simulated result agrees well with the experimental result. [ABSTRACT FROM AUTHOR]

Abstract: Evolution of electrical properties and thin-film transistor characteristics of amorphous indium gallium zinc oxide (IGZO) thin films synthesized by RF sputtering with O2 plasma immersion has been examined. O2 plasma immersion results in an enhancement in the Hall mobility and a decrease in the electron concentration; and the transistor performance can be greatly improved by the O2 plasma immersion. X-ray photoelectron spectroscopy analysis indicates that the effect of O2 plasma immersion on the electrical properties and the transistor performance can be attributed to the reduction of the oxygen-related defects in the IGZO thin films. [Copyright &y& Elsevier]

Abstract: In this work, we report a non-destructive approach, which is based on the spectroscopic ellipsometry (SE) and a multi-layer model, to calculate the depth profiling of the dielectric functions of SiO2 films containing Si nanocrystals (nc-Si) synthesized by ion beam technique. Each sub-layer of SiO2 film containing nc-Si is represented by Maxwell-Garnett effective medium approximation (EMA). Then the nc-Si dielectric functions are extracted from the best fittings of SE results. Finally, the dielectric functions of each sub-layer of SiO2 containing nc-Si are calculated with Maxwell-Garnett EMA using the previously extracted information of nc-Si, and thus the depth profile of dielectric functions for the SiO2 thin film containing the nc-Si is obtained. [Copyright &y& Elsevier]

In this letter, we report a novel approach to quantitative determination of charge trapping near the channel/drain edge caused by electrical stress. The approach is based on gate-controlled-diode (GCD) measurement. By measuring the GCD drain current in the band-to-band tunneling regime and using the formula developed in this work, the change of the Si surface field resulting from the charge trapping can be calculated instantly, and then the charge trapping is determined quantitatively. It is found that the stress-time dependence of both the surface field change and the charge trapping follow a power law. [Copyright &y& Elsevier]

The gate-controlled-diode (GCD) characteristic of a deep submicron MOSFET is changed dramatically following a Fowler–Nordheim (FN) injection. The changes can be explained by the trap generation on the Si surface close to the channel/drain edge and the interface trap generation in the channel region. By examining the change in the reverse drain current under accumulation and inversion in the GCD measurements, the information of trap generation in the surface region close to the channel/drain edge is obtained (note that the trap generation in this region could be different from that in other interface regions); and by measuring the reverse drain current under depletion, the interface trap generation in the channel region is obtained. [Copyright &y& Elsevier]

Abstract: In this work, we have investigated the performance and reliability of a Flash memory based on silicon nanocrystal synthesized with very-low energy ion beams. The devices are fabricated with a conventional CMOS process and the size of the nanocrystal is ∼4 nm as determined from TEM measurement. Electrical properties of the devices with a tunnel oxide of either 3 nm or 7 nm are evaluated. The devices exhibit good endurance up to 105 W/E cycles even at the high operation temperature of 85 °C for both the tunnel oxide thicknesses. For the thicker tunnel oxide (i.e., the 7-nm tunnel oxide), a good retention performance with an extrapolated 10-year memory window of ∼0.3 V (or ∼20% of charge lose after 10 years) is achieved. However, ∼70% of charge loss after 10 years is expected for the thinner tunnel oxide (i.e., the 3-nm tunnel oxide). [Copyright &y& Elsevier]

In this letter, we report an approach to quantitative study of the relationship between the oxide charge trapping over the drain extension due to electrical stress and the off-state drain leakage current. It is found that positive charge trapping over the drain extension leads to a significant increase in the off-state drain current if the edge direct tunneling (EDT) is dominant in the drain current but in contrast, it leads to a reduction in the drain current if the band-to-band tunneling in the Si surface is dominant. A quantitative relationship between the charge trapping and the off-state drain leakage current in the EDT regime is established. From the measurement of the off-state current in the EDT regime, the charge trapping can be determined by using the approach developed in this study. [ABSTRACT FROM AUTHOR]

MOS structure with Si nanocrystals embedded in the gate oxide close to the gate has a much larger capacitance compared to a similar MOS structure without the nanocrystals. However, charge trapping in the nanocrystals reduces the capacitance dramatically, and after most of the nanocrystals are charged up the capacitance is much smaller than that of the MOS structure without nanocrystals. An equivalent-capacitance model is proposed to explain the phenomena observed. [ABSTRACT FROM AUTHOR]

This brief reports a study of charge injection-induced edge charge trapping in the gate oxide overlapping the drain extension which has an impact on the drain leakage current. The edge charge trapping is determined for the gate oxide thickness of 6.5, 3.9, and 2.0 nm by using a simple approach to analyze the change of the band-to-band tunneling current measured with a three-terminal gate-controlled-diode configuration. The edge charge trapping has a strong dependence on the gate oxide thickness, and it is different from the charge trapping in the oxide over the channel. A plausible explanation for both the oxide thickness dependence of the edge charge trapping and the difference between the edge charge trapping and the charge trapping over the channel is presented. [ABSTRACT FROM AUTHOR]

Examines the growth of polycrystalline silicon-boron (Si-B) layer on recrystallized amorphous silicon. Presence of SiB[sub 6] in Si-B layer; Mobility of the B atoms in Si-B layer during thermal annealing; Reduction of B diffusivity by SiB[sub 6].

Demonstrates the room temperature deposition of thin silicon dioxide film by reactive laser ablation from a c-silicon target in a cw low pressure oxygen radio frequency magnetron plasma. Significance on the reactivity of an oxygen gas; Description on the radio frequency hollow oval magnetron system; Demonstration of water free film deposition.

In recent years, the weight binarized neural network (BNN) technology has made great progress. However, neural networks with binarized inputs and binarized weights suffer from low accuracy in pattern recognition or inefficiency in hardware implementation. This work proposes a spatio-temporal binary neural network (STBNN) to solve this problem. STBNN has binary network input/output, binary neuron input/output, and binarized weights, and it integrates the computationally expensive batch normalization (BN) operation widely used in previous BNNs into the neuron threshold. STBNN can largely save computing resources and storage space while maintaining high accuracy (e.g., 98.0% on the MNIST test set). Using binary input (0 or 1) and binarized weight (±1), the product of input and weight can be realized by a 1-bit Signed AND operation instead of multiplication operation in hardware implementation, thus significantly reducing computing resources, memory requirements, and power consumption. The results show that compared with a 32-bit multi-layer perceptron (MLP)-based hardware design, the STBNN-based hardware design typically reduces these three indicators by 84.2%, 96.4%, and 96.7%, respectively. This work provides an effective method to construct hardware-friendly neural network models and a guide for designing an extremely hardware-saving neural network processor. [ABSTRACT FROM AUTHOR]

An abstract of the article "Decreased nitric oxide production after cardioplegia-induced cardiac arrest under cardiopulmonary bypass induced cardiomyocytic apoptosis by activation of the unfolded protein response," by C. H. Yeh is presented.

An abstract of the study "Bradykinin Limits Cardiomyocytic Apoptosis Via Restoration of Nitric Oxide After Cardioplegic Arrest," by C. H. Yeh and colleagues, is presented.

Abstract: Incorporating the recent bond order–length–strength correlation mechanism [C.Q. Sun, Phys. Rev. B 69 (2004) 045105] to the size dependence of Auger photoelectron coincidence spectra of Cu nanoparticles with and without being passivated has enabled us to gain quantitative information about the 2p and 3d level energies of an isolated Cu atom and their shift upon bulk formation. The developed approach also enabled us to discriminate the effect of crystal-field screening from the effect of valence recharging (due to surface passivation and substrate–particle interaction) on the binding energies to the electrons at different energy levels of a specimen. [Copyright &y& Elsevier]

Abstract In this paper, tungsten oxide (WO 3 ) thin films and hybrid polyelectrolyte have been synthesized by solution-based processes to form solid-state electrochromic devices (ECDs). Electrochromic properties of the ECDs have been investigated, focusing on the near-infrared (NIR) region of the light spectrum. By optimizing the applied impulse voltage and WO 3 film thickness, a coloration efficiency of 78.8 cm2/C has been achieved in the ECD under the impulse voltage of ± 2.5 V. In addition, at the same voltage, the response time of 2.5 s and 15.8 s was obtained for bleaching and coloring, respectively. The fast switching between colored and bleached states is due to the porous structure of solution-processed WO 3 films that facilitates injection/release of Li ions. Stable current-time profiles have been obtained during cyclic measurements with alternating impulse voltages within 6 × 103 s, indicating excellent reversibility in the ECDs. The solid-state ECDs based on WO 3 films are promising to be used in applications requiring NIR-related optical modulation such as smart windows. [ABSTRACT FROM AUTHOR]

In this Letter, an asynchronous spike-driven processor based on gated recurrent neural network algorithm for electrocardiogram (ECG) cardiac arrhythmias detection has been designed. Based on the processor, the proposed ECG detection model, containing a many-to-many gated recurrent unit layer and a fully connected layer, can achieve a high classification overall accuracy of 97.8% using the MIT-BIH arrhythmia database. The processor was fabricated in 55-nm 1P6M CMOS technology. It integrates about 1.4 million logic gates, including 40 KB of on-chip memory within a $4.0\,{\rm mm}^2$4.0mm2 die area. The test chip consumes 6.28 mW at real-time operation frequency (200 MHz) with 1.2 V core supply voltage and $2.65\,{\rm \mu} {\rm W}$2.65μW at 1 kHz. [ABSTRACT FROM AUTHOR]

By dissolving gallium chloride (GaCl 3 ), indium chloride (InCl 3 ), zinc acetate dihydrate [Zn(OAc) 2 ·2H 2 O] and monoethanolamine (MEA) into a solvent of 2-methoxyethanol, the IGZO ink was synthesized. Five types of IGZO ink were prepared with different molar ratios of In:Ga:Zn, which can be used for ink-jet printing process. The thermal behaviors of IGZO ink with different formulas were investigated and the ideal annealing temperature for film formation was found to be ∼450 °C. Based on the prepared ink, amorphous IGZO thin films were directly printed on the glass substrate with a FujiFilm Dimatix ink-jet printer, followed by a thermal annealing at 450 °C for 1 h. The surface morphology, crystal structure, optical transmittance, electron mobility and carrier concentration were characterized and investigated. The ink-jet printed amorphous IGZO thin films fabricated in this work can be used as switching medium in flexible resistive random access memory devices. [ABSTRACT FROM AUTHOR]

Abstract: During magnetron sputtering deposition of SrBi2Ta2O9 thin films, oxygen gas is introduced in the deposition chamber to compensate the oxygen loss during sputtering. In this paper, the influence of oxygen partial pressure is systematically investigated in sputtering of Sr0.8Nd0.3Bi2.5Ta2O9+x thin films, using X-ray diffraction, X-ray photoelectron spectroscopy and field emission scanning electron microscopy. The studies confirm that at various oxygen partial pressure Nd3+ ions substitute into the bismuth layered perovskite structure, preferentially at the Sr2+ site. The deposition rate, composition, microstructure and polarization properties of the films highly depend on the oxygen partial pressure. [Copyright &y& Elsevier]

Abstract: For many years, the development of effective laser machining techniques for making glass-based microcomponents and devices has been a critical factor in the birth of new photonic and biomedical microsystems. In this article, the characteristics and abilities of excimer lasers for micromachining of a wide range of glass materials are reviewed and studied. Following the introduction, the special features of excimer lasers are discussed. The typical micromachining system used for glass materials is presented. Then, the fundamental micromachining parameters and the associated morphologies of machined surfaces are evaluated. The approaches by controlling the ablation rate for making the curve surfaces are specifically formulated. Although a wide range of commercially available glasses is covered in this article, two types of the most widely used glasses, borosilicate glass and fused silica, are thoroughly examined to illustrate the complexity in micromachining the glass materials. The procedures to machine single, arrayed, curved microstructures are described. The utilizations of these procedures for making microneedles, optical waveguides, submicron grating, and microlenses are specifically demonstrated. Finally, recommendations for future efforts are presented. [Copyright &y& Elsevier]

Abstract: The refractive indices of textured indium tin oxide (ITO) and zinc oxide (ZnO) thin films were measured and compared. The ITO thin film grown on glass and ZnO buffered glass substrates by sputtering showed distinct differences; the refractive index of ITO on glass was about 0.05 higher than that of ITO on ZnO buffered glass in the whole visible spectrum. The ZnO thin film grown on glass and ITO buffered glass substrates by filtered vacuum arc also showed distinct differences; the refractive index of ZnO on glass was higher than that of ZnO on ITO buffered glass in the red and green region, but lower in the blue region. The largest refractive index difference of ZnO on glass and ITO buffered glass was about 0.1 in the visible spectrum. The refractive index variation was correlated with the crystal quality, surface morphology and conductivity of the thin films. [Copyright &y& Elsevier]

Abstract: In this work, we have investigated the capacitance–voltage (C–V) and conductance–voltage (G–V) characteristics of silicon nanocrystals (nc-Si) distributed in the gate oxide very near the SiO2/Si interface of a Metal-Oxide-Semiconductor (MOS) structure. The MOS structure is found to be sensitive to only the positive voltage stress from which charging of the nanocrystals causes a negative flatband voltage shift. At the same time, a large conductance peak is observed due to the energy loss via the neutral-nanocrystal paths near the SiO2/Si interface. Besides, breakdown of the dielectric film containing the nc-Si is also observed from the G–V characteristic. [Copyright &y& Elsevier]

Abstract: In this work, the unique synthesis of mechanically milled silicon nanocrystals (Si nc) embedded in tetraethylorthosilicate (TEOS) thin films is reported. The Si nc are required to be synthesized externally via inexpensive mechanical milling before it is mixed with the TEOS solution for spin coating. Si nc with a range of sizes, from 10 to 25nm, have been synthesized using mechanical milling. These milled Si nc and milled Si nc embedded in TEOS thin film are characterized by differential thermal analysis (DTA), Raman spectroscopy and photoluminescence excitation (PLE). The defects, such as non-bridging oxide hole centers (NBOHCs), in amorphous SiO2 are found to be the most probable dominant mechanism for the PL of milled Si nc embedded in films. The milled Si nc embedded in TEOS thin film is further developed into MOS capacitor. Charge trapping in Si nc with a V FB shift of 0.4V is observed. [Copyright &y& Elsevier]

Abstract: TaN-Cu nanocomposite thin films used as materials for thin-film resistors (TFR) were prepared by magnetron dc reactive co-sputtering. With the introduction of N2 gas flow into the Ar/N2 plasma, different phases of β-Ta, Ta2N, TaN, and Cu can be observed, resulting in different electrical properties of TaN-Cu thin films. After deposition, rapid thermal processing (RTP) was applied to anneal the thin films at 400 °C for 2, 4, 8 min in Ar ambient, causing the nucleation and growth of Cu nanoparticles. It was found that the resistivity and TCR changed after various annealing time due to the counteractions among the quantum effect caused by the nanosized Cu particles, the amorphous matrix, and loosened TaN matrix after Cu precipitation. The most obvious increase in the resistivity was found when annealing for 4 min, and the most decrease in TCR occurred after 4 min annealing. In general, a suitable combination of annealing time, Cu at.%, and N2 flow rate is required to reach near-zero TCR value. Longer annealing time requires less Cu at.% to reach zero-TCR point. [Copyright &y& Elsevier]

TaN–Cu nanocomposite thin films used as materials for TFR (thin film resistor) were prepared by reactive co-sputtering of Ta and Cu in the plasma of N2 and Ar. After deposition, the films were annealed using rapid thermal processing (RTP) at 400 °C for 2, 4, 8 min, respectively to induce the nucleation and grain growth of Cu. The results reveal that temperature coefficient of resistivity (TCR) values will increase with the increase of Cu content for both the as-deposited and annealed films. The increase of nitrogen will result in higher resistivity and more negative TCR. At a constant nitrogen flow rate, the resistivity and TCR may increase or decrease with the increase of annealing time depending on the Cu content. In general, to reach near-zero TCR value, more copper is needed to compensate the negative effect caused by Ta–N. Thus, electrical properties of thin films can be characterized as functions of N2 flow rate, Cu concentration and annealing time. [Copyright &y& Elsevier]

Lead magnesium niobate-lead titanate (PMN-PT) is an intriguing candidate for applications in many electronic devices such as multi-layer capacitors, electro-mechanical transducers etc. because of its high dielectric constant, low dielectric loss and high strain near the Curie temperature. As an extension of our previous work on Ta-doped PMNT-PT aimed at optimizing the performance and reducing the cost, this paper focuses on the effect of Pb volatilization on the dielectric properties of 0.77Pb(Mg[sub 1/3](Nb[sub 0.9]Ta[sub 0.1])[sub 2/3])O[sub 3]-0.23PbTiO[sub 3]. The dielectric constant and loss of the samples are measured at different frequencies and different temperatures. The phase purity of this compound is determined by X-ray diffraction pattern. It is found that the volatilization during sintering does influence the phase formation and dielectric properties. The best condition is sintering with 0.5 g extra PbO around a 4 g PMNT-PT sample. [ABSTRACT FROM AUTHOR]

Adding the effect of surface bond contraction to the Hamiltonian of an extended solid leads to a new mechanism indicating that the blue-shift in the photoluminescence (PL) of CdS and CdSe nanosolids arises from the surface-relaxation-enhanced binding energy and the PL shift depends on the portion of surface atoms of the solid. Consistency between predictions and observations evidences that a surface bond contracts more than it does on a flat surface when the surface curvature increases and that the Cd–Se bond contracts faster than the Cd–S bond when the solid approaches to the lower end of size limit. [ABSTRACT FROM AUTHOR]

Abstract: The authors report the fabrication of ZnO-based metal-oxide-semiconductor field effect transistors (MOSFETs) with a high quality SiO2 gate dielectric by photochemical vapor deposition (photo-CVD) on a sapphire substrate. Compared with ZnO-based metal-semiconductor FETs (MESFETs), it was found that the gate leakage current was decreased to more than two orders of magnitude by inserting the photo-CVD SiO2 gate dielectric between ZnO and gate metal. Besides, it was also found that the fabricated ZnO MOSFETs can achieve normal operation of FET, even operated at 150°C. This could be attributed to the high quality of photo-CVD SiO2 layer. With a 2μm gate length, the saturated I ds and maximum transconductance (G m ) were 61.1mA/mm and 10.2mS/mm for ZnO-based MOSFETs measured at room temperature, while 45.7mA/mm and 7.67mS/mm for that measured at 150°C, respectively. [ABSTRACT FROM AUTHOR]

This paper proposed an energy-efficient deep convolution neural networks coprocessor (DCNNs-CP) architecture for multi-object detection applications based on deep learning algorithms. The DCNNs-CP can support both convolutional layers and fully connected layers to accelerate various mobile deep learning algorithms. It also supports maximum and mean pooling operations through a separate pooling module structure. Besides, a reconfigurable activation function module supporting four nonlinear functions is also realized in this coprocessor. The DCNNs-CP chip was implemented in 55 nm CMOS process technology and occupied the 4 mm2 die area. The DCNNs-CP supports 8-bit and 16-bit fixed-point data precision and achieves a peak performance of 3.4 Tops / W at 1.2 V supply voltage and a maximum frequency of 500 MHz, represent 2.13x improvements over reported hardware accelerators. Besides, the chip achieves 0.85 Tops / W · mm 2 energy efficiency per area and 34.0 Tops / W · MB energy efficiency per memory (on-chip memory), making it suitable to be integrated with the mobile devices. [ABSTRACT FROM AUTHOR]