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This study investigates the impact of gate bias stress with and without light illumination in a-Si:H thin film transistors. It has been observed that the I–V curve shifts toward the positive direction after negative and positive gate bias stress due to interface state creation at the gate dielectric. However, this study found that threshold voltages shift negatively and that the transconductance curve maxima are anomalously degraded under illuminated positive gate bias stress. In addition, threshold voltages shift positively under illuminated negative gate bias stress. These degradation behaviors can be ascribed to charge trapping in the passivation layer dominating degradation instability and are verified by a double gate a-Si:H device.

All-optical processing and generation are regarded as a key solution to achieve ultrahigh bitrate communication in next generation. Silicon based optical waveguides have been widely developed, including ultrafast electrical-optical modulator, splitter, wavelength generator, and etc. However, the carrier relaxation issues as well as inevitable two-photon absorption in communication regions limit its application in developing ultrafast all-optical modulation and supercontinuum generation. Recently, large optical bandgap materials have been utilized to demonstrate nonlinear waveguide applications for all-optical processing. Tantalum pentoxide (Ta 2 O 5 ) used to serve as gate dielectric and optical coatings in optoelectronic devices due to its high dielectric constant and refractive index properties. Nowadays, Ta 2 O 5 with high optical nonlinearity and free of nonlinear absorption let it suitable in developing small footprint, high power operation optical devices [1, 2].

Nonlinear wavelength generations by using the optical waveguides are more compact, low cost, and efficient than using the traditional solid state systems [1], and the generated broadband light sources can be utilized in optical coherence tomography, frequency metrology, optical communications, and many other. In this work, the high quality of tantalum pentoxide (Ta 2 O 5 ) micro-ring resonator has been fabricated to realize the low power parametric frequency conversion in the communication region. Figure 1 shows the illustration and scanning electron microscope (SEM) image of Ta 2 O 5 based micro-ring resonator. The width/height of the ring waveguides is set as 1.5μm/0.7μm for the anomalous dispersion, which is a key element to minimize the phase mismatch in the parametric frequency conversion process. By fitting the transmission spectrum of the Ta2O5 ring resonator, the load quality factor is ∼50000 and the loss coefficient is ∼0.5cm−1. The unload quality factor is estimated to be ∼180000, which is the best record of Ta 2 O 5 based micro-ring resonator [2].

The surface morphology in polycrystalline silicon (poly-Si) film is an issue regardless of whether conventional excimer laser annealing (ELA) or the newer metal-induced lateral crystallization (MILC) process is used. This paper investigates the stress distribution while undergoing long-term mechanical stress and the influence of stress on electrical characteristics. Our simulated results show that the nonuniform stress in the gate insulator is more pronounced near the polysilicon/gate insulator edge and at the two sides of the polysilicon protrusion. This stress results in defects in the gate insulator and leads to a nonuniform degradation phenomenon, which affects both the performance and the reliability in thin-film transistors (TFTs). The degree of degradation is similar regardless of bending axis (channel-length axis, channel-width axis) or bending type (compression, tension), which means that the degradation is dominated by the protrusion effects. Furthermore, by utilizing long-term electrical bias stresses after undergoing long-tern bending stress, it is apparent that the carrier injection is severe in the subchannel region, which confirms that the influence of protrusions is crucial. To eliminate the influence of surface morphology in poly-Si, three kinds of laser energy density were used during crystallization to control the protrusion height. The device with the lowest protrusions demonstrates the smallest degradation after undergoing long-term bending.

Tantalum pentoxide (Ta2O5) of a large bandgap material has recently utilized to demonstrate nonlinear optical waveguide applications due to its superior linear and nonlinear optical properties [1][2], including low absorption loss coefficient in visible to infrared regions, high Kerr coefficients, and free of nonlinear absorption. In this work, the thermal-optical coefficient of tantalum pentoxide has been investigated experimentally by using a micro-ring resonator structure. Taking the advantage of index-sensitively property of ring resonator, the material with ultralow thermal-optical coefficient is easily to be measured and analyzed by using a ring waveguide structure. The cross-section of Ta2O5 based micro-ring resonator is set as 1.5μm*0.7μm, and the diameter of ring resonator is set as 100μm. By increasing the substrate temperature of micro-ring resonator, the variation of resonant wavelength of micro-ring resonator is recorded accordingly. The central wavelength of micro-ring resonator is red-shifted from 1543.430 nm to 1543.586 nm when the substrate temperature increases from 20 to 40°C. By considering the thermal-optical and thermal expansion effect of micro-ring resonator, the thermal-optical coefficient of Ta2O5 is estimated to be 6.8×10−6 / K at ~1550 nm. The thermal-optical coefficient of Ta2O5 is ten times of magnitude less than those of conventional III–V semiconductors, indicating that Ta2O5 supports the development of thermal-insensitive devices, such as sub-multiplexer and filter element.

Transparent undoped semiconductor indium oxide films were deposited by using a long-throw rf magnetron sputtering at room temperature. It was found that the variation of oxygen content in sputtering gas has a strong influence on the microstructure and electrical properties of the films. The electrical resistivity varying from 3.5 × 10−2 to 4.7 × 104 Ω-cm for oxygen contents ranging from 0 to 50 % was obtained. The optical band gap decreases as the oxygen content increases, and the average visible transmittance of the indium oxide is ~85 %. To put into practice, the as-sputtered indium oxide was employed as a channel of thin film transistors on glass substrate with a channel length, 6 μm, and a channel width, 20 μm. Its saturation mobility, threshold voltage, and on/off ratio were obtained to be 9.4 V−1 s−1, 1.5 V, and 2.2 × 107. To approach a flexible device, a plastic substrate is employed to replace the rigid substrate, glass; and the relative parameters, saturation mobility, threshold voltage, and on/off ratio, are also measured to be 8.2 V−1 s−1, 1.8 V, and 1.4 × 106, respectively.

By analyzing the temperature-dependent transmission spectrum of a Ta2O5 micro-ring resonator, the thermal-optical coefficient at the optical communication wavelength regime has been determined. The temperature-dependent resonance wavelength shift of the resonator with radius 50 µm was measured as 7.8 pm/K, and the thermal-optical coefficient at ∼1543 nm was estimated to be 6×10−6 /K. Furthermore, a power-dependent transmission of the micro-ring resonator was performed to characterize the effects of local heating and nonlinear absorption. No significant power-dependent wavelength shift and asymmetric response were observed in the optical wavelength up to 125 mW. This suggests the absence of nonlinear absorption and thermal expansion effects in the Ta2O5 ring resonator. The Ta2O5 waveguide is potentially a superior candidate for applications in optical communication systems or high-power nonlinear waveguides due to its thermal stability, thermal insensitivity, and absence of nonlinear absorption.

In this work, for the first time, to the best of our knowledge, an anomalous dispersion CMOS-compatible Ta2O5 waveguide was realized, and broadband on-chip supercontinuum generation (SCG) was accordingly demonstrated. When pumped at a center wavelength of 1056 nm with pulses of 100 fs duration and peak power of 396 W, a supercontinuum ranging from 585 nm to 1697 nm was generated, comprising a bandwidth of more than 1.5 octaves and leading to an efficient SCG source. The excellent performance for Ta2O5 to generate SCG benefits mainly from its high nonlinear refractive index, which enhances the efficiency of the nonlinear conversion process.

We fabricated waveguide resonators with high thermal stability using tantalum pentoxide thin film covered with PECVD silicon dioxide cladding. Without complex athermal design, low temperature dependence of 7.4 pm/°C and 8.15 pm/°C were measured in waveguide Bragg gratings (WBG) and Fabry-Perot resonator sandwiched by a pair of identical WBG mirrors, respectively. Suggested by semi-analytical perturbation calculations, the athermal properties of tantalum pentoxide waveguide grating are attributed not only to the low thermo-optical coefficient in tantalum pentoxide thin film but also to the strong chromatic dispersion of the guided modes. Guidelines are proposed to design waveguide-based frequency devices of low thermo-optical effect without complex athermal design.

At bending radius smaller than 2 mm, flexible low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs) suffer from strong uniaxial mechanical stress and demonstrate severe degradation of electrical characteristics. Our previous study showed that repetitive mechanical uniaxial bending damages the gate insulator, causing carriers to trap into it. Here, degradation after channel width-axis direction bending was found to be more pronounced than after channel length-axis bending. In order to alleviate this degradation, an organic structure flexible LTPS TFT was proposed to enhance the mechanical stress endurance. After 100000 iterations of uniaxial mechanical bending at ${R} = 2$ mm, degradation nearly disappeared in devices with this organic trench structure.

This letter demonstrates a mobility enhancing method using a multi-active layer structure in oxide TFTs. The active layers are deposited in sequence according to their different conductivities, which can be performed with different materials or different process conditions. The multi-active layer comprises bottom, middle, and top layers, forming a carrier-confinement structure. The middle layer has a higher carrier concentration, while bottom and top layers have lower ones. In this way, the main channel current flows through the middle layer, and this avoidance of the gate insulator/active layer and active layer/passivation interface leads to higher mobility. In this work, the multi-layer oxide TFTs shows better mobility of 46.5 cm2/Vs when compared to any single layer.

A conductive DBR electrode fabricated using the single Indium tin oxide (ITO) conductive material is proposed. The high refractive index of the dense ITO film was achieved by RF sputtering at room temperature and the porous ITO film with low refractive index was prepared by applying supercritical CO2 (SCCO2) treatment at 60 °C on gel-coated ITO thin films. The index contrast of the ITO bilayers was higher than 0.5 at a wavelength of 550 nm. In addition, small deviations on the optical thickness of the ITO bilayers were observed during the DBR stacking processes. For the DBR comprising 4 periods ITO bilayers, the reflectance and sheet resistance of 72.8% and 35 Ω/ were achieved.

The authors obtained older adults' self-rated judgments about the quality of their activity engagement considered as a whole (global activity evaluation) and, using cross-sectional survey data, tested the ability of such judgments to predict well-being. Participants were 460 community-dwelling older adults who responded to (1) global activity evaluations, (2) activity participation frequency scales, and (3) indices of life satisfaction, depression, and physical and mental health-related quality of life. Regression analyses indicated that global activity evaluations had a stronger relationship to psychosocial outcome indices than did participation frequency ratings, although both measurement approaches were associated with statistically significant predictions. However, global evaluations and participation frequency ratings were approximately equal in their ability to predict physical health-related quality of life. These relationships were fairly consistent across ethnic groups. Overall, the results suggest that ideally the two strategies for assessing activity should be incorporated in future research on activity and occupational therapy practice.

Electrical characteristics and the effect of hotcarriers are investigated in via-contact-type a-InGaZnO thinfilm transistors. Current-voltage as well as capacitance-voltage measurements are utilized to investigate the impact of top gate bias on device characteristics as well as degradation behaviors caused by a hot-carrier stress. It is found that the redundant source/drain electrodes in via-contact type devices can screen the electric field established by a top gate bias and have significant influence on the device characteristics. Hot-carrier stress brings about electron trapping in the etch stop layer below the redundant electrodes, and this is further verified through modulating the energy band structure by applying a top gate bias during the capacitance-voltage measurement.

This study investigates bipolar resistance switching memory in a fabricated Pt/GaOx/TiN device. Gallium oxide sputtered in ambient Ar shows a change in resistance ratio of two orders of magnitude. The enhancement of resistance ratio is also observed in the gallium oxide layer when deposited in ambient Ar/O2. The X-ray photoelectron spectroscopy analysis shows that this gallium oxide in ambient Ar/O2 can reduce the number of defects and enhance the stability of switching behavior. An analysis of current transport mechanism in the high resistance state indicates that the larger effective thickness can be attributed to the higher oxygen concentration, and can increase the resistance value of the high resistance state.

This paper studies the effect of doping on BON-based resistive switching characteristics. Typical bipolar resistive switching behavior can be observed in Pt/BON/TiN and Pt/BON:Gd/TiN devices. The conductive path(s) of the Pt/BON/TiN is vacancy-dominated while the Pt/BON:Gd/TiN is metal-dominated. Additionally, there is an atypical bipolar resistive switching in the Gd-doping device. This atypical characteristic has not only a size effect, but also a lower operating current. The resistance transitions are due to the variation in conductance of the switching layer, which is clearly influenced by the different area size. A mechanism is proposed to explain this atypical characteristic.

In this study, the Pt/IGO/TiN resistance random access memory (ReRAM) is investigated by the fabrication of co-sputtering the Ga2O3 and In2O3 targets to form the InGaOx (IGO) film. The Pt/GaOx/TiN structure was fabricated as comparison device. In addition to the bipolar resistance switching characteristic shown in GaOx film, the unipoar switching characteristic is also obtained in IGO device. The switching mechanisms between bipolar and unipolar in the IGO device are investigated by measuring the resistance values in various temperatures. From the results, the proportional relationship between resistance value and temperature among the bipolar switching characteristics illustrates that the switch is caused by the generation/recombination of oxygen vacancies. However, the unipolar switching behaviors can be attributed to metallic filament due to the trend of increasing resistance with the increasing temperature.

In this study, we fabricated and analyzed resistance switching characteristics for resistance random access memory (RRAM) in a Pt/In 2 O 3 /SiO 2 /TiN structure. By applying opposing electric fields to perform a soft breakdown of the In 2 O 3 /SiO 2 insulating bi-layer, different switching behaviors are exhibited. When positive forming voltage was applied to the TiN electrode to soft breakdown the device, the resistance switching behavior was dominated by the bipolar mode. However, the negative voltage forming process exhibited both unipolar switching characteristics in addition to a bipolar switch mode. In order to analyze the composition of the conduction path and resistance switching mechanism, resistance value trends versus temperature was extracted and showed that the conduction paths of bipolar and unipolar modes are dominated by oxygen vacancies and metallic filament, respectively. Hence, metallic filament was considered to be formed by the migration of indium ions because the unipolar characteristic was only present during negative bias forming condition.

This letter studies the hot-carrier effect in indium–gallium–zinc oxide (IGZO) thin film transistors with symmetric and asymmetric source/drain structures. The different degradation behaviors after hot-carrier stress in symmetric and asymmetric source/drain devices indicate that different mechanisms dominate the degradation. Since the C–V measurement is highly sensitive to trap states compared to the I–V characterization, C–V curves are utilized to analyze the hot-carrier stress-induced trap state generation. Furthermore, the asymmetric C–V measurements C GD (gate-to-drain capacitance) and C GS (gate-to-source capacitance) are used to analyze the trap state in channel location. The asymmetric source/drain structure under hot-carrier stress induces an asymmetric electrical field and causes different degradation behaviors. In this work, the on-current and subthreshold swing (S.S.) degrade under low electrical field, whereas an apparent V t shift occurs under large electrical field. The different degradation behaviors indicate that trap states are generated under a low electrical field and the channel-hot-electron (CHE) effect occurs under a large electrical field.

We propose a multi-layer dye-sensitized solar cell (DSSC). Conventional DSSC components use a singular TiO2 particle size and a mono-layer active layer, but we demonstrate a multi-layer and multi-scale TiO2 particle based DSSC. Doping with large TiO2 particles can produce light scattering inside the DSSC component. Light scattering effects reduce TiO2 absorption at wavelengths of 200-300 nm. The unabsorbed light zig-zags between the Pt back electrode layer and the substrate, and enhances the Ru-dye absorption. To enhance the scattering, we doped the active layer with 20 wt% of large diameter TiO2. The multi-layer DSSC increases efficiency by about 15% compared with standard DSSCs.

Organic dispersion agents can effectively decrease the surface roughness of films. Here, films containing organic dispersion agents are used to produce metal-insulator-metal structures. It was found that addition of Triton caused films to become denser, and thicker, and the leak current of devices to decrease by 10 times compared with that without Triton because of its uniform dispersion in the films. The resulting films were used as the insulator layer of thin film transistors containing a semiconductor layer of evaporated pentacene. The interface between the insulator and semiconductor layers was found to affect the arrangement of pentacene, and O2 plasma was used to improve the interface activity to increase the order of the pentacene molecules and enhance the carrier mobility of the devices.

This paper investigates degradation behavior induced by the self-heating effect for InGaZnO (IGZO) thin-film transistors (TFTs). Both the surrounding oxide and other thermal insulating materials, as well as the low thermal conductivity of the InGaZnO layer itself, cause the self-heating effect in InGaZnO TFTs. The heated channel layer enhances the threshold voltage shift, and the evolution of threshold voltage shift is found to be dominated by charge-trapping effects. Moreover, a nonuniform distribution of channel carrier concentration leads to an uneven temperature distribution throughout the IGZO active layer, which results in the asymmetrical degradation behavior after the self-heating operation. Further verifications indicate that the degree of the threshold voltage shift is only dependent on stress power, regardless of stress Vg, Vd, and channel length. Further, two-stage dependence of the threshold voltage shift on dynamic stress frequency is found.

A simple and cost-effective approach is proposed as an alternative to conventional oxygen plasma treatment to modify surface property of Indium tin oxide (ITO) anode of a fluorescent organic light-emitting diode (OLED). This was achieved by treating the ITO anode in supercritical CO 2 (SCCO 2 ) fluids with hydrogen peroxide (H 2 O 2 ). The SCCO 2 /H 2 O 2 treatment yielded an ITO work function of 5.35 eV after 15 min treatment at 85 °C and 4000 psi, which was significant higher than 4.8 eV of the as-cleaned ITO surface and was slightly less than 5.5 eV of the ITO surface treated by oxygen plasma. The highest work function achieved was 5.55 eV after 45 min SCCO 2 /H 2 O 2 treatment. The SCCO 2 /H 2 O 2 treatment can be used to tailor the ITO work function through changing the operation pressure of the treatment. In addition, the correlated dependence of OLED performance on the ITO anodes with and without the treatments was investigated. The maximum power efficiency of 1.94 lm/W was obtained at 17.3 mA/cm 2 for the device with 15 min SCCO 2 /H 2 O 2 treatment at 4000 psi. This power efficiency was 19.3% and 33.8% higher than those of the oxygen plasma treatment and as-clean, respectively. The improvement in device efficiency by the SCCO 2 /H 2 O 2 treatments can be attributed to enhanced hole injection and balance in charge carriers due to increased work function and surface energy of the ITO anodes.

Optical spectra broadening as a result self-phase modulation in a channel waveguide fabricated on a high quality tantalum pentoxide (Ta

In this work, nonlinear optical properties of high quality Ta2O5 film has been investigated by self-phase-modulation technique. The nonlinear refractive index(n2) as high as 2×10−14 cm2/W at 800nm was obtained. In addition, nearly analytical formula for modifying n2 was discussed.

Knowledge of the construct of occupation remains fragmented within traditional social science disciplines. In this paper, we aim to provide a theoretical synthesis by explicating the unique properties of occupation in relation to the self within social science discourse. Occupations relate to other social science constructs in three ways: (a) they recruit a set of associated changes into a person's life; (b) they serve a person's ability to achieve important goals; and (c) they act as a mirror by reflecting multiple dimensions of the self. Key characteristics of occupation such as its experiential salience and its repetitional flavor powerfully amplify its significant role in affecting self-relevant outcomes. Occupation represents a crucial playing field that profoundly affects the unfolding of human lives. Therefore, the continued pursuit of occupational science is warranted and can uniquely contribute to an improved understanding of the self.

This letter studies the hot-carrier effect in indium-gallium-zinc oxide (IGZO) thin film transistors with symmetric and asymmetric source/drain structures. The different degradation behaviors after hot-carrier stress in symmetric and asymmetric source/drain devices indicate that different mechanisms dominate the degradation. Since the C-V measurement is highly sensitive to the trap state compared with the I-V characterization, C-V curves are utilized to analyze the hot-carrier stress-induced trap state generation. Furthermore, the asymmetric C-V measurements CGD (gate-to-drain capacitance), CGS (gate-to-source capacitance) are useful to analyze the trap state location in the channel. For the asymmetric device structure, the different source/drain structure under hot-carrier stress-induces an asymmetric electrical field and causes different degradation behaviors. In this work, the on-current and subthreshold swing (S.S.) degrade under low electrical field, whereas the apparent Vt shift occurs under a large electrical field. The different degradation behaviors indicate that trap states are generated under low electrical field and the channel-hot-electron (CHE) effect occurs under a large electrical field.

A novel approach has been developed to fabricate hills-like hierarchical structured TiO2 photoanodes for dye-sensitized solar cells (DSSCs). The appropriately aggregated TiO2 clusters in the photoanode layer could cause stronger light scattering and higher dye loading that increases the efficiency of photovoltaic device. For detailed light-harvesting study, different molecular weights of polyvinyl alcohol (PVA) were used as binders for TiO2 nanoparticles (P-25 Degussa) aggregation. A series of TiO2 films with dissimilar morphology, the reflection of TiO2 films, absorbance of attached dye, amount of dye loading, and performance of fabricated DSSC devices, were measured and investigated. An optimized device had energy conversion efficiency of 4.47% having a higher dye loading and good light harvesting, achieving a 23% increase of short-circuit current J(sc) in DSSCs.

This letter investigates the reliability issues of HfO 2 /Ti 1 − x N x metal-oxide-semiconductor field effect transistor in terms of static and dynamic stress. The results indicate threshold voltage ( V th ) instability under dynamic stress is more serious than that under static stress, owning to transient charge trapping within high-k dielectric. Capacitance–voltage techniques verified that electron trapping under dynamic stress was located in high-k dielectric near the source/drain (S/D) overlap region, rather than the overall dielectric. Furthermore, the V th shift clearly increases with an increase in dynamic stress operation frequency. This phenomenon can be attributed to the fact that electrons injecting to the S/D overlap region have insufficient time to de-trap from high-k dielectric. We further investigated the impact of different Ti 1 − x N x composition of metal-gate electrode on charge trapping characteristics, and observed that V th shift decreases significantly with an increase in the ratio of nitride. This is because the nitride atoms diffusing from the metal gate fill up oxygen vacancies and reduce the concentration of traps in high-k dielectric.

This article examines the relation between occupation and experience and explores the potentiality of occupation as means to create experiences that matter. First, a transactional view is used to explicate the nature of occupation and experience. Second, a plausible way in which occupation can be powerfully positioned as catalyst for transformation is explored. By paying attention to the ‘ends-in-view’, possible courses of action surrounding occupational choices are envisaged to anticipate desirable experiences. Such an approach can be used to reinforce a positive and meaningful occupational trajectory that promotes health and well-being. The limitations and implications of employing such an approach are also discussed.

High hydrophilic/hydrophobic contrast surfaces on polyethylene terephthalate (PET) substrates were formed by shadow mask technique in electron cyclotron resonance generated sulfur hexafluoride plasma atmosphere. The X-ray photoelectron spectroscopy (XPS) analyses indicate that the unmasked PET surfaces contained a high proportion of the CF2–CF2 groups, and therefore were hydrophobic with large water contact angle. However, the surface wettability was found to increase drastically on the masked PET surfaces. This could be resulted from a mass of COF (acid fluoride) compounds observed by XPS on the masked film surfaces. The COF compounds could react with atmospheric moisture to form –COOH groups, which in turn increased the surface wettability. In addition, the surface wetting property of the masked areas was found to change significantly with the plasma treatment time, the mask-to-substrate distance and the storage time after the treatment. The best contract in water contact angle obtained from the treated PET samples was larger than 100° after 168 h of storage.

This letter investigates various oxygen concentra- tions in indium oxide films which induce different resistance switching behaviors, including two self-compliance behaviors and a two-step set process. The accumulated oxygen ions produce an oxygen-rich indium oxide film, which can be considered as a variable series resistor after the forming process. Analyses indicate that the lower self-compliance current can be attributed to this larger variable series resistor from the additional oxygen ions. The more significant oxidation reaction decreases the current of the high resistance state. Hence, power consumption can be reduced effectively.

The influence of tensile mechanical strain on gate-induced floating-body effect (GIFBE) in advanced partially depleted SOI n-MOSFETs was investigated. Both drain current and mobility enhance after applying strain due to the reduction of average transfer effective mass. However, it was found that the GIFBE becomes serious under the mechanical strain. To explain this phenomenon, we first clarify the mechanism of GIFBE using different operation conditions. The experiment results indicate that the GIFBE can be attributed to the anode hole injection (AHI) rather than the widely accepted mechanism of electron band (EVB) tunneling. Based on the AHI model, the enhanced GIFBE under the mechanical strain is mainly due to the narrowing of band gap induced by the strain in the poly-gate.

In this paper, the NiSi 2 /SiN X compound NCs (CNCs) structure is studied to further improve the retention. To introduce the nitride based traps, NiSi 2 was also sputtered in the mixture gas of Ar (50 sccm) and NH 3 (10 sccm) at room temperature, and the NiSi 2 /SiN X CNCs can be easily formed after rapid thermal annealing. In addition, standard memory devices with single and double NiSi 2 nanocrystal were also prepared for comparison. By XPS analyses, the nanocrystals fabricated in the ambiance of NH 3 can be confirmed to be composited of NiSi 2 and SiN X compound. According to memory characteristics results, better retention characteristic of device with single-layer NiSi 2 /SiN X compound nanocrystal NVMs can be observed after 10 4 s, raises from 50% to 72% in comparison with the control sample, even better than the double-layer NiSi 2 nanocrystal, 58%. Indeed, the formation of NiSi 2 /SiN X CNCs can improve the retention characteristics remarkably due to the additional tunnel barrier and deep traps in the nitride.

Structures and surface chemical composition of indium tin oxide (ITO) thin films prepared by long-throw radio-frequency magnetron sputtering technique have been investigated. The ITO films were deposited on glass substrates using a 20 cm target-to-substrate distance in a pure argon sputtering environment. X-ray diffraction results showed that an increase in substrate temperature resulted in ITO structure evolution from amorphous to polycrystalline. Field-emission scanning electron microscopy micrographs suggested that the ITO films were free of bombardment of energetic particles since the microstructures of the films exhibited a smaller grain size and no sub-grain boundary could be observed. The surface composition of the ITO films was characterized by X-ray photoelectron spectroscopy (XPS). Oxygen atoms in both amorphous and crystalline ITO structures were observed from O 1 s XPS spectra. However, the peak of the oxygen atoms in amorphous ITO phase could only be found in samples prepared at low substrate temperatures. Its relative peak area decreased drastically when substrate temperatures were larger than 200 °C. In addition, a composition analysis from the XPS results revealed that the films deposited at low substrate temperatures contained high concentration of oxygen at the film surfaces. The oxygen-rich surfaces can be attributed to hydrolysis reactions of indium oxides, especially when large amount of the amorphous ITO were developed near the film surfaces.

The Ta2O5-based micro-ring resonator with an unloaded quality factor of 182,000 has been demonstrated to realize efficient nonlinear wavelength generation. The propagation loss of the resonator is 0.5 cm−1, and the buildup factor of the ring resonator is estimated to be ∼50. With a high buildup factor of the ring structure, the four-wave-mixing (FWM) conversion efficiency of −30 dB is achieved in the resonator with a pump power of 6 mW. Based on power-dependent FWM results, the nonlinear refractive index of Ta2O5 is estimated to be 1.4×10−14 cm2/W at a wavelength of ∼1550 nm. The demonstration of an enhanced FWM process in the Ta2O5-based micro-ring cavity implies the possibility of realizing FWM-based optical parametric oscillation in a Ta2O5-based micro-ring resonator.

Aim: To find associations between types of activity participated in by healthy Asian retirees and 7 quality of life (QOL) domains. Methods: Fiftyfour retireeswere recruited. An inventory of 16 types of activity was used. Satisfaction levels on QOL domains were measured using modified Comprehensive QOL Scale Adult questionnaire. Multivariate linear regression analysis was performed. Results: Socialactivities had positive impact on material well-being, health, productivity, and safety satisfaction. Participation in fine art and travel activities also reportedhigher satisfaction in QOL domains. Conclusion: Social engagement is crucial inenhancing QOL. Artistic and travel activities help retirees build closer relationships with others.

TCR signals induce the nuclear localization of NFATc proteins, which are removed from the nucleus after rephosphorylation by glycogen synthase kinase 3 and other kinases. Rapid nuclear export might allow continuous monitoring of receptor occupancy, making the transcriptional response proportional to the duration of TCR/CD28 signaling. To investigate this possibility, we analyzed mice in which T cells express a NFATc1 variant (NFATc1nuc) with serine-to-alanine changes at the glycogen synthase kinase 3 phosphorylation sites. NFATc1nuc T cells have constitutively nuclear NFATc1, enhanced T cell activation in vivo, and calcineurin-independent proliferation in vitro. NFATc1nuc T cells are hypersensitive to TCR/CD3 stimulation, resulting in enhanced proliferation and cytokine production that is independent of CD28 costimulation. These results support the notion that CD28 inhibits nuclear export of NFATc transcription factors. In addition, NFATc1nuc destabilizes a positive feedback loop in which NFATc1 activates its own transcription as well as its targets, such as CD40 ligand and Th1/Th2 cytokines.