Search

ZnO is one of the most widely used inorganic sunscreens, owing to its fine particle size and UV light shielding capability. However, powders at nanosizes can be toxic and cause adverse effects. The development of non-nanosized particles has been slow. The present work investigated synthesis methods of non-nanosized ZnO particles for ultraviolet protection application. By altering the starting material, KOH concentration, and input speed, the ZnO particles can be obtained in different forms, including needle type, planar type, and vertical wall type. Cosmetic samples were made by mixing different ratios of synthesized powders. The physical properties and the UV blockage efficacy of different samples were evaluated using scanning electron microscopy (SEM), X-ray diffraction (XRD), particle size analyzer (PSA), and ultraviolet/visible (UV/Vis) spectrometer. The samples with 1:1 ratio of needle-type ZnO and vertical wall-type ZnO exhibited superior light blocking effect owing to improved dispersibility and prevention of particle agglomeration. The 1:1 mixed sample also complied with the European nanomaterials regulation due to the absence of nanosized particles. With superior UV protection in the UVA and UVB regions, the 1:1 mixed powder showed potential to be used as a main ingredient in UV protection cosmetics.

To achieve good long-term temperature stability in devices used in energy-conversion applications, this study is aimed at developing combined ceramics, referred to as PZN-PMN-PZT, comprising Pb(Zn1/3Nb2/3)O3 (PZN) and Pb(Mn1/3Nb2/3)O3 (PMN), which are typical relaxor ferroelectric materials, and Pb(Zr,Ti)O3 (PZT). The piezoelectric properties were compared based on several parameters according to the change in the composition ratio between relaxor materials, amounts of Sb2O3 dopant, and Zr/Ti ratio in the PZT system. Finally, we established optimal poling conditions to improve the electrical properties of the optimized piezoelectric material, based on the evaluation of ceramic properties according to the applied voltage during the poling process. The optimized composition of the investigated piezoelectric ceramics is represented by 0.14PZN-0.06PMN-0.80PbZr0.49Ti0.51 + 0.3 wt.% CuO + 0.3 wt.% Fe2O3 with 0.1 wt.% Sb2O3 doping, which yielded the superior properties (d33 = 361 pC/N, Qm = 1234, Tc = 306 °C).

Purpose: The aim of this study was to analyze the prevalence of depression, anxiety, somatization disorder, and adjustment disorder in older patients diagnosed with exudative age-related macular degeneration (AMD) and to evaluate the relationship between exudative AMD and psychological disease.Methods: The 2016 Health Insurance Review and Assessment Service-Aged Patient Sample was applied in this study. The subjects were divided into two groups: AMD patients undergoing intravitreal injection treatment and a control group. Comorbidities were evaluated using the Charlson Comorbidity Index.Results: A total of 1,319,052 subjects were selected, of which 3,134 were in the exudative AMD group receiving intravitreal injections. The average age of the subjects was 74.7 ± 6.7 years, and 41.8% were male. In patients with exudative AMD, the prevalence of depression, anxiety, somatization disorder, and adjustment disorder were 16%, 20%, 0.5%, and 0.4%, respectively; in particular, the prevalence of depression and adjustment disorder were significantly higher than in the control group. In multivariate regression analysis, exudative AMD was a significant factor of depression (odds ratio [OR] 1.2, 95% confidence interval [CI] 1.08-1.31, p < 0.001) and adjustment disorder (OR 2.47, 95% CI 1.47-4.18, p < 0.001). However, the association between AMD and anxiety or somatization disorder was not statistically significant.Conclusions: Exudative AMD showed a significant association with psychiatric disease, such as depression, and requires close clinical attention.

To classify 2.5-µm-scale fine dust and measure its concentration, research was conducted to produce a fine-dust sensor utilizing computational fluid dynamics simulation and microelectromechanical system processes, and the measurement system was manufactured for the sensor. The virtual impactor was designed to classify particles in the air above and below 2.5 µm, and the cut-off diameter of 2.5 µm at an acceleration nozzle length of 83.2 µm was obtained by verifying this impactor through flow-analysis simulation. The microheater was then designed to measure the mass of the classified particle by adsorbing it onto the surface acoustic wave resonator placed on the lower part of the flow channel using thermophoretic force. The conditions where the classified particles are completely adsorbed on the surface acoustic wave resonator through the heater were calculated using numerical modeling and the results were verified through the simulation. The fine dust sensor based on the designed surface acoustic wave resonator is composed of the upper, middle, and lower parts including the heater, virtual impactor, and surface acoustic wave resonator and SMA connector, respectively, and the micro-fan controlling the total flow. Each part was produced using the microelectromechanical system process, assembled, and finally finished. Moreover, the evaluation system was produced in this study to assess the developed sensor. The flow of air controlled through the flowmeter was sprayed into a dust bottle filled with hollow silica powder to scatter the powder, which flowed into the system with the air, making the environment similar to one with fine dust present. The change in radio-frequency resonance characteristics, such as those before and after exposure to the fine dust environment, and insertion loss after the surface cleaning were observed, and a sensitivity of, detection limit of, and restoration rate after surface cleaning exceeding 99.9% were obtained.

In this study, a [0001]-plane planar-type ZnO ceramic powder material with a high aspect ratio ranging from 20:1–50:1 is synthesized using the electrolyte collected from zinc air battery power generation. This high aspect ratio may be due to the Zn(OH)2-4 anion dissolved in the electrolyte. The obtained planar-type ZnO exhibits excellent formulation stability and applicability, even when formulated as a cosmetic with a single inorganic ingredient. Compared to commercial ZnO or TiO2 powders, relatively better protection against infrared and ultraviolet (UV) radiation is realized due to its asymmetric characteristics, with a width of approximately 1 μm and thickness of tens of nm. The synthesized planar-type ZnO is mixed with nanosized ZnO or TiO2 commercial powders and formulated into various combinations to achieve a high UV protection rate and heat-blocking effect. In particular, the addition of planar-type ZnO to nanosized TiO2 powders increases the heat-blocking effect, and improves the applicability and formulation stability of the cosmetic formulation, despite the decrease in turbidity. Among all the ceramic powder combinations examined in this study, the best UV protection rate and heat-blocking effect are obtained when the synthesized planar-type ZnO is mixed with microsized and nanosized TiO2.

The mechanism for the deposition of zinc to form porous thin films is not clearly understood. In this study, a modified direct current (DC) sputtering system was used to deposit polycrystalline porous zinc thin films on an amorphous glass substrate to elucidate the mechanism. Subsequently, the properties of the thin films, such as its film thickness, the average particle size, and its porosity, were investigated under different experimental parameters, including pressure, DC discharge power, and the gas ratio between Ar and He. The plasma properties were also studied using a Langmuir probe. An increase in deposition pressure and DC discharge power was found to increase the deposition thickness and the particle size in the thin films whereas an increase in the He content increased the thickness and decreased the particle size. The investigation of the growth mechanism revealed that the zinc particles were oriented in different planes at early and later stages of deposition. Moreover, the properties of the thin films were observed to be affected by the energy loss of the zinc atoms and the bonding force between the substrate and the zinc particles. This understanding of the mechanism of thin-film formation will help to guide the optimization of experimental parameters in the fabrication of high-quality thin films.

In the current study, we prepared a LixLa3Zr2O12 ((Al, Ta) LLZO) powder doped with 0.2 mol of Al and Ta using the sol-gel method and subsequently used it to fabricate solid electrolyte pellets. In pellets with lithium content of 6.2 and 6.82 mol, a cubic phase and a lithium-deficient pyrochlore mixed-phase were respectively observed. However, when the lithium content was 8.06 mol, a lithium-excess phase was also observed. Meanwhile, at 7.44 mol lithium, the (Al, Ta) LLZO ceramic pellets showed a pure cubic garnet phase with no secondary phase. When lithium was added excessively, a non-granular morphology was observed at the (Al, Ta) LLZO fracture surface in which the grains were tightly bonded by the liquid phase formed during sintering. Nyquist plots of the pellets showed that the effect of grain boundaries was eliminated and the pellets exhibited a high lithium ion conductivity of 4.26 × 10−4 S/cm. Using spin coating and multi-step heat treatment, we deposited LiCoO2 (LCO) thin films on (Al, Ta) LLZO pellets to form cathodes. There was no significant interdiffusion between the LCO cathode and (Al, Ta) LLZO solid electrolyte and morphological analysis indicted that a thin interfacial layer (~10 nm) was formed between the LCO and the electrolyte. Finally, we demonstrated an all-solid-state rechargeable battery in the form of a coin cell comprising of an LCO cathode, Li metal anode, and (Al, Ta) LLZO solid electrolyte, which could yield a discharge capacity of ~100 mAh/g.

A conical-shaped Si dioxide nano-pattern was employed to sapphire substrate in order to improve the light extraction efficiency of light-emitting diodes. The conical-shaped Si dioxide nano-patterns were fabricated on a 2-inch sapphire wafer using direct imprinting of hydrogen silsesquioxane material. A blue-LED structure was grown on conical-shaped silicon-dioxide nano-patterned sapphire substrates. Photoluminescence and electroluminescence measurements were used to confirm the effectiveness of the nanoscale Si oxide patterned sapphire. An improvement in the luminescence efficiency was observed when nanoscale Si oxide patterned sapphire substrate was used. 1.5 times higher PL intensity and 1.6 times higher EL intensity were observed for GaN LED structure grown on nanoscale Si oxide patterned sapphire, compared to LED structure grown on conventional flat sapphire wafer.

Background Picosecond-domain laser treatment using a microlens array (MLA) or a diffractive optical element (DOE) generates micro-injury zones in the epidermis and upper dermis. Objective To investigate interactive tissue reactions between MLA-type picosecond laser pulses and cohesive polydensified matrix hyaluronic acid (CPMHA) filler in the dermis. Methods In vivo rats with or without CPMHA pretreatment were treated with a 1064-nm picosecond-domain neodymium:yttrium-aluminum-garnet (Nd:YAG) laser using an MLA or DOE. Skin samples were obtained at post-treatment days 1, 10, and 21 and histologically and immunohistochemically analyzed. Results Picosecond-domain Nd:YAG laser treatment with an MLA-type or a DOE-type handpiece generated fractionated zones of pseudo-cystic cavitation along the lower epidermis and/or upper papillary dermis at Day 1. At Day 21, epidermal thickness, dermal fibroblasts, and collagen fibers had increased. Compared to CPMHA-untreated rats, rats pretreated with CPMHA showed marked increases in fibroblasts and collagen fibers in the papillary dermis. Immunohistochemical staining for the hyaluronic acid receptor CD44 revealed that MLA-type picosecond laser treatment upregulated CD44 expression in the basilar epidermis and dermal fibroblasts. Conclusions We suggest that the hyaluronic acid-rich environment associated with CPMHA treatment may enhance MLA-type picosecond-domain laser-induced tissue reactions in the epidermis and upper dermis.

This study investigates the effects of the Zn/Ni composition ratio and doping materials on the piezoelectric properties of PZNN-PZT ceramics for the fabrication of piezoelectric ceramics with excellent characteristics. A soft relaxor was used to improve the electrical characteristics and sinterability. The ceramics were fabricated with a base composition ratio of 0.13Pb((Zn1–xNix)1/3Nb2/3)O3–0.87Pb(Zr0.5Ti0.5)O3. The columbite phase was formed by reacting NiO and Nb2O5, which have low reactivity, as the first calcination, and the columbite precursor method was applied for the second calcination with PbO. Although the pellet was produced by sintering at a relatively low temperature of 950 °C, we obtained a dense ceramic with a high density of 7.9 g/cm3 . To improve the quality factor in the composition with a Ni/(Ni + Zn) molar ratio of 0.1, the doping materials MnO2, Fe2O3, CuO, and Bi2O3 were added and their properties were confirmed. Pure perovskite phases were formed in the ceramics of all compositions and doping materials. In particular, the PZNN-PZT ceramics doped with 0.3 wt% MnO2 showed a piezoelectric coefficient of 348 pC/N, electromechanical coupling factor of 0.59, mechanical quality factor of 345, and Curie temperature of 316 °C, which are excellent piezoelectric characteristics.

We conducted computational fluid dynamic (CFD) simulations to improve the thickness uniformity of cluster-sputtered porous metal films. The cluster sputtering equipment was divided into a module where the sputtered metal atoms condensed and cluster nanoparticles formed and a chamber where porous metal films were deposited. To optimize the equipment geometry, we performed simulations and deposition experiments for various planar nozzle positions and nozzle-to-substrate distances in the module. The simulated gas velocity distribution 25 mm above the substrate exhibited a similar tendency to the thickness distribution of the deposited porous Cu films. When a 4-mm nozzle was located 40 and 240 mm from the module center and substrate, respectively, the simulated gas velocity distribution exhibited uniformity to within 8.4% for the substrate with a 70-mm radius. The thickness uniformity and the deposition rate of the deposited porous Cu films were 9.3% and 2 µm/min, respectively, using equipment with the same geometry.

In this study, two different conical-shape nano-patterns were fabricated on the 2-inch diameter sapphire wafer in order to improve the efficiency of light-emitting diodes. The conical-shape nano-patterns were fabricated on the sapphire wafer using a nanoimprint technique and dry etching method. A blue LED structure was grown on the nanoscale-patterned sapphire substrates. The photoluminescence and electroluminescence were measured to confirm the effectiveness of the nano-scale patterns. An improvement in the luminescence efficiency was observed in case that nano-patterned sapphire substrate was used; a 1.44 times-higher photoluminescence intensity and a 1.5 times-higher electroluminescence intensity were observed, compared to those of the light-emitting diodes structure grown on a conventional flat sapphire wafer.

Infrared scene projector (IRSP) is a tool for evaluating the performance of infrared (IR) sensors by generating and projecting virtual IR images. Developing IRSPs with a high frame rate is necessary to evaluate high-speed IR sensors. To develop IRSPs with high frame rates, porous anodic aluminum oxide (AAO) with high thermal conductivity is proposed as a constituent material of IR emitters, which emit infrared rays in IRSPs. Through structure design and fabrication, an AAO-based IR emitter having a suspended structure with a gap of $1~\mu \text{m}$ from the substrate was fabricated. The operating speed was obtained by confirming the change in the temperature, which was calculated by measuring the change in resistance after applying the step-function voltage. The operating speed of the AAO-based IR emitter was found to increase with decrease in the leg length of the device. The frame rate of the device with a $5~\mu \text{m}$ leg length was found to be 155.3 Hz, twice as fast as the conventional silicon nitride (Si3N4)-based emitters with the same leg length and pitch. Consequently, it is possible to develop the high-speed IRSPs with the application of AAO for emitter. [2019-0191]

Hf

A multilayer piezoelectric material was fabricated using piezoelectric materials with low-temperature sintering capabilities and high piezoelectric coefficients to develop a functionally superior piezoelectric speaker with a large-displacement deformation. A soft relaxor was utilized to prepare the component materials, with the optimized composition of the investigated piezoelectric ceramics represented by 0.2Pb((Zn0.8Ni0.2)13Nb23)O3−0.8Pb(Zr0.5Ti0.5)O3. Li2CO3 was added to assist the low-temperature sintering conducted at 875 °C, which yielded a multilayer piezoelectric material with superior properties (d33&nbsp, = 500 pC N−1, kp&nbsp, = 0.63, g33&nbsp, = 44 mV N−1). A multilayer piezoelectric actuator with a single-layer thickness of ~40 µm and dimensions of 12 × 16 mm2 was fabricated by tape casting the prepared green sheets. Finite element analysis revealed that the use of a PEEK film and a smaller silicone–rubber film as a composite in the diaphragm realized optimal frequency-response characteristics, the vibrations generated by the piezoelectric element were amplified. The optimal structure obtained via simulations was applied to fabricate an actual piezoelectric speaker with dimensions of 20 × 24 × 1 mm3. The actual measurements exhibited a sound pressure level of ~75 dB and a total harmonic distortion ≤15% in the audible frequency range (250–20,000 Hz) at an applied voltage of 5&nbsp, Vp.

To facilitate a high-dynamic-range operation of mid-wavelength infrared focal-plane arrays, a low-power, high-sensitivity readout integrated circuit (ROIC) is proposed. In this ROIC, the capacitor-reset block employing clock signals adopts a double-edge-triggered flip-flop instead of a single-edge-triggered one to reduce errors within the final output signals. In addition, an asynchronous clock-gating technique is employed to control clock-signal usage in accordance with the input signal, thereby reducing the power consumption within two-dimensional arrays. The proposed low-power, high-sensitivity ROIC has been realized with a 0.18-μm 1-poly 6-metal CMOS process. It has been confirmed that in cases involving low input-signal current, the power consumption of the proposed ROIC can be reduced to approximately 2% of that of conventional ROICs.

We have developed a facile method to fabricate Ag-doped SnO2 composite film prepared via one-step kinetic spraying process. We used supersonic/subsonic nozzles to accelerate powders to their maximum kinetic energies when bombarding the substrates; no post-treatment was required. Under optimized conditions, sensors fabricated from SnO2-based films with and without Ag nanoparticles (NPs) were smooth and about 7 µm in thickness. To improve CO-sensing performance, Ag NPs (to less than 1 wt%) were added to SnO2 films. The sensor response to CO of the film with 1 wt% Ag was up to 20-fold better than that of the Ag-free film, even a low CO concentration of 500 ppm. We thus confirmed that addition of a small amount of Ag NPs to a SnO2 film increased electron transport and improved catalysis of oxygen ionization on the film surface. Therefore, we have developed a facile method of Ag-doping in composite gas sensor and this crack-free composite gas sensor was found to be highly sensitive to CO gas.

Test devices of unpassivated, single-layer passivated, and double-layer passivated samples were fabricated to analyze the enhancement of thermal stability for shutter-less infrared (IR) image sensors. In this study, double-layer passivation (SiOx/SiNx) was proposed to avoid the oxygen-diffusion from unpassivated or single-layer (SiOx) passivated Nb:TiO2−x (TNO) samples. Before fabricating the test device, high-temperature (450 °C) annealing was carried out under oxygen-rich ambient conditions to improve the thermal stability by reducing the number of oxygen vacancies in the as-deposited TNO samples. The double-layer passivated sample showed higher thermal stability than the other samples. The structural and bolometric properties were also studied for all passivated samples and the obtained results attested that the properties seemed to be almost similar for different passivation layers. It was found that the proposed double-layer passivated TNO sample could provide enhanced thermal stability for future shutter-less IR sensors.

Metal oxide semiconductors are widely used as gas sensing materials; thus, improving their gas sensing properties is of some interest. The microstructure of a SnO2 film was controlled using the thermal evaporation technique at a relatively high process pressure. Scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) analysis were used to characterize microstructures, crystallinity, particle size, and the surface area that was dramatically altered as a function of the process pressure. In all cases, SnO2 films had interconnected network structures with open pores; continuous grain growth was observed through the neck between the SnO2 nanoparticles. The responses of sensors fabricated at different depositional pressure were evaluated by monitoring changes in the electrical resistance of CO gas. The gas sensor deposited at 0.2 Torr showed a high response and short response time owing to its high porosity (97%) and nano-sized particles (8.4 nm). The results confirm that porosity and particle size play key roles in determining the gas response.

We propose a novel read-in integrated circuit (RIIC) for infrared scene projectors (IRSPs) providing three modes for infrared (IR) scene adaptive operation. Conventional IRSPs have difficulty in simultaneously satisfying IR-scene fidelity-related parameters such as the thermal dynamic range and thermal resolution, since there is a tradeoff between them. To overcome the limitation, a triple-mode RIIC is proposed. A prototype was fabricated using a $0.35~\mu \text{m}$ CMOS process and measurements were performed to determine its performance. The estimated thermal dynamic range varies from 275–385 K to 275–745 K according to the operating mode. Furthermore, the estimated thermal resolution at temperatures below 300 K reaches only up to 30 mK in every mode when using a 12-bit digital-to-analog converter.

For the effective deicing of the windows of electric vehicles, we fabricated asymmetric multilayered transparent (AMT) film heaters exhibiting a low resistance (5.4 Ω/sq.) and high visible transmittance (88%), resulting in the highest figure of merit (759) reported to date. Also, the simulated transmittance of the AMT films better matched the experimental results when considering the microstructure of the reaction layer between the Ga-doped ZnO and Ag layers. Herein, an unconventional approach considering heat transfer by conduction is described because heat loss from the thick glass (>3 mm) inevitably occurs in the real-world application of vehicle windows. We formulated and simultaneously solved two derivative heat transfer equations considering the thermal loss in the thick glass and heat transfer in the heating films to accurately predict the temperature of the outside glass. To verify our model, we performed a heating test by inserting heated windows in a small-scale automobile model and were able to accurately predict deicing time and heating rates.

Photovoltaic devices that convert solar energy into electrical energy are a promising solution to resolve environmental problems the world is facing today. Among the various photovoltaic system, dye-sensitized solar cells (DSSCs) has been regarded as a new generation of the photovoltaic device due to the low cost and simple fabrication process. However, the current design of DSSCs shows insufficient conversion efficiency. To solve this problem, we increase the optical path length by trapping the incident light using a diffraction grating with high reflectance. We numerically investigate the effect of geometric parameters on the reflectance of diffraction gratings in DSSC system. Based on the simulation results, we propose an optimized geometry of diffraction grating that reflects the outgoing light and traps the incident light. The optimized geometry of the diffraction grating increase in the reflectance about 80% when it is compared to that without the diffraction grating.

This paper proposes a new readout integrated circuit for high-dynamic-range mid-wavelength infrared (MWIR) focal plane arrays. The proposed readout circuit is characterized by asynchronous self-controlled two-gain-mode operation and multiple reset control according to the input signal for each pixel. The proposed circuit was designed and fabricated using a 0.18- $\mu \text{m}$ 1-poly 6-metal CMOS process. Measurement results indicate that it has a dynamic range of 99.2 dB with a good signal-to-noise ratio for a wide range of input signals at a high frame rate of 200 Hz. The proposed circuit is expected to be useful for MWIR detectors used in missile application systems.

A dummy-gate-assisted n-type metal–oxide–semiconductor field-effect transistor (DGA n-MOSFET) structure was modified to allow the use of a silicon-on-insulator (SOI) substrate and evaluated for robustness against the total ionizing dose effect. The modified DGA n-MOSFET on the SOI substrate suppressed all possible radiation-induced leakage current paths by isolating both the drain and source from the sidewall oxide using a p+ layer and from the buried oxide using dummy gates and halo doping. Simulated ${V} _{\textsf {g}}$ – ${I} _{\textsf {d}}$ curves indicated that the modified DGA n-MOSFET on the SOI substrate effectively reduces the leakage current caused by accumulated radiation exposure. Furthermore, experimental gamma radiation exposure data showed that the modified device exhibited good performance, even after exposure up to 300 krad (Si). All devices used in the experiments were fabricated using the 180-nm commercial fabrication process by the CSOI7RF of Global Foundries, formerly IBM Microelectronics.

We have introduced a new fabrication process for a CO gas sensor using a kinetically sprayed Cu thin layer, followed by oxidation at 250 °C. The resulting 200 nm-thick CuO thin layer exhibited semi-transparent optical properties. The as-fabricated CO gas sensor was tested under two conditions with varying CO gas concentration ranging from 1000 to 5000 ppm and operating temperatures of 200, 250, and 300 °C: (1) a reaction time of 600 s and a recovery reaction time in an air atmosphere of 1800 s; and (2) a gas reaction time of 1200 s and a recovery time of 7200 s. As a result, the sensor response showed its improvement under a high operating temperature of 300 °C with a reaction time of 600 s and a recovery time of 1800 s regardless of the CO gas concentration. In contrast, the response of the CuO gas sensor showed its maximum value of 0.209 at a lower temperature of 200 °C, due to a sufficient recovery time of 7200 s. Therefore, we have proved that a kinetically sprayed CuO thin layer can be operated with varying CO gas concentration, as well as varying the temperature and time, to be useful as a gas sensor.

The rapidly growing Li-ion battery market has generated considerable demand for Li-ion batteries with improved performance and stability. All-solid-state Li-ion batteries offer promising safety and manufacturing enhancements. Herein, we examine the effect of substitutional doping at three cation sites in garnet-type Li7La3Zr2O12 (LLZO) oxide ceramics produced by a sol&ndash, gel synthesis technique with the aim of enhancing the properties of solid-state electrolytes for use in all-solid-state Li-ion batteries. Building on the results of mono-doping experiments with different doping elements and sites&mdash, Al, Ga, and Ge at the Li+ site, Rb at the La3+ site, and Ta and Nb at the Zr4+ site&mdash, we designed co-doped (Ga, Al, or Rb with Nb) and tri-doped (Ga or Al with Rb and Nb) samples by compositional optimization, and achieved a LLZO ceramic with a pure cubic phase, almost no secondary phase, uniform grain structure, and excellent Li-ion conductivity. The findings extend the current literature on the doping of LLZO ceramics and highlight the potential of the sol&ndash, gel method for the production of solid-state electrolytes.

In this study, a novel IR projector driver that can minimize nonuniformity in electric circuits, using a dual-current-programming structure, is proposed to generate high-quality infrared (IR) scenes for accurate sensor evaluation. Unlike the conventional current-mode structure, the proposed system reduces pixel-to-pixel nonuniformity by assigning two roles (data sampling and current driving) to a single transistor. A prototype of the proposed circuit was designed and fabricated using the SK-Hynix 0.18 &micro, m CMOS process, and its performance was analyzed using post-layout simulation data. It was verified that nonuniformity, which is defined as the standard deviation divided by the mean radiance, could be reduced from 21% to less than 0.1%.

HfxZr1−xO2 (HZO) thin films have excellent potential for application in various devices, including ferroelectric transistors and semiconductor memories. However, such applications are hindered by the low remanent polarization (Pr) and fatigue endurance of these films. To overcome these limitations, in this study, HZO thin films were fabricated via plasma-enhanced atomic layer deposition (PEALD), and the effects of the deposition and post-annealing temperatures on the density, crystallinity, and electrical properties of the thin films were analyzed. The thin films obtained via PEALD were characterized using cross-sectional transmission electron microscopy images and energy-dispersive spectroscopy analysis. An HZO thin film deposited at 180 °C exhibited the highest o-phase proportion as well as the highest density. By contrast, mixed secondary phases were observed in a thin film deposited at 280 °C. Furthermore, a post-annealing temperature of 600 °C yielded the highest thin film density, and the highest 2Pr value and fatigue endurance were obtained for the film deposited at 180 °C and post-annealed at 600 °C. In addition, we developed three different methods to further enhance the density of the films. Consequently, an enhanced maximum density and exceptional fatigue endurance of 2.5 × 107 cycles were obtained.

Piezoelectric material properties were optimized to develop materials for an ultrasonic vibrator targeting a high vibration efficiency. Herein, novel materials were developed using a composition represented by 0.08Pb(Ni1/3Nb2/3)O3-0.07Pb(Mn1/3Nb2/3)O3-0.85Pb(Zr0.5Ti0.5)O3 + 0.3 wt.% CuO + 0.3 wt.% Fe2O3 with 0.3 wt.% Sb2O3 doping. A ceramic shape with a thickness of 2 mm was optimized using finite element analysis software, and high values of coupling factors (0.54) and mechanical quality factors (1151) were obtained. This ceramic was used to fabricate a bio-beauty device (frequency = 1 MHz), and the manufactured ultrasonic vibrator indicated that the actuator oscillated with the maximum amplitude at a frequency of 1.06 MHz.

In this study, we prepared and characterized Nb-doped Li7La3Zr2−xO12 (LLZNO) powder and pellets with a cubic garnet structure by using a modified sol-gel synthesis and hot pressing. LLZNO powder with a very small grain size and cubic structure without secondary phases could be obtained by using a synthesis method in which Li and La sources in a propanol solvent were mixed together with Zr and Nb sources in 2-methoxy ethanol. A pure cubic phase LLZNO pellet could be fabricated from the prepared LLZNO and an additional 6-wt% of Li2CO3 powder by hot pressing at 1050 °C and 15.8 MPa. The hot-pressed LLZNO pellet with a relative density of 99% exhibited a very dense surface morphology. The total Li ionic conductivity of the hot-pressed LLZNO was 7.4×10 −4 S/cm at room temperature, which is very high level compared to other reported values. The activation energy for ionic conduction was estimated to be 0.40 eV.

A QCW LD pumped linearly polarized Nd3+:YAG/V3+:YAG laser operating at 1444 nm with high peak power of 62 kW is demonstated for the first time. The polarization extinction ratio of the 1444 nm output beam was higher than 1000:1 and the highest second-harmonic generation efficiency at 722 nm was 62.8%. A compact high-peak-power polarized Nd:YAG laser can be used as the master oscillator for a high energy system. In particular, a 722 nm laser is a viable source for biomedical applications such as photoacoustic imaging, oximetry, and tattoo removal.

This paper presents a p-MOSFET latch-based nuclear event detector signal-processing circuit which is implemented using a commercial standard 0.35- μ m CMOS process. A positive-feedback loop consisting of a p-MOSFET with a common-source configuration and a photocurrent compensation MOSFET are used to offset the transient radiation effects. Additionally, a timer circuit containing an on-chip timer capacitor serves to reduce the response time. To mitigate the total ionizing dose effect, all n-MOSFETs are laid out using dummy gate-assisted n-MOSFETs. The measured response time of the fabricated chip is 12.2 ns. After measuring the electrical characteristics of the fabricated chip, the chip is exposed to 60Co gamma rays at a dose of 1.14 Mrad (Si). Even after exposure to radiation, the performance of the irradiated chip is nearly identical to that of a non-irradiated chip. To evaluate the upset threshold with regard to the dose rate of the fabricated chip, the chip is also exposed to prompt gamma rays with different dose rates, and the measured dose rate upset threshold is found to exceed 1.9 × 107rad(Si)/s.