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The development of efficient CuSCN hole transport layers is crucially important for achieving high photovoltaic performance in inorganic perovskite devices. In this study, the effects of electrodeposition charge density on the morphological/microstructural and electrical properties and the formation mechanism of electro-deposited CuSCN films are investigated and discussed. The results indicate that the charge density is the key factor that governs not only the thickness, but also morphological, electrical, and surface properties of the electro-deposited CuSCN films. For the energy band diagram property, we found that when the charge density is 120 mC cm−2 (named as CD120), the valance band of CuSCN near ITO work function. This excellent property can efficiently improve the photovoltaic performance of inorganic perovskite devices, where ITO and CuSCN are employed, owing to the reduction of energy barrier. Among the films electro-deposited at different charge densities, the CD120 exhibits the highest mobility, possibly due to the excess amount of SCN in the thin film.

Zr-Cu based thin-film metallic glass (TFMG) has good glass-forming ability and the addition of a third element can create a chaotic system capable of inhibiting the nucleation and growth of crystals. This study focused on TFMGs made with Zr, Cu, and Ti in various compositions deposited via high-impulse magnetron sputtering on silicon and 304 stainless-steel substrates. Detailed analysis was performed on the microstructure and surface characteristics of the resulting coatings. Transmission electron microscopy revealed that the multilayer structure changed to a nanocrystalline structure similar to an amorphous coating. The excellent hydrophobicity of Zr-Cu-Ti TFMGs can be attributed to their ultra-smooth surface without any grain boundaries. The excellent antimicrobial effects can be attributed to a hydrophobic surface resisting cell adhesion and the presence of copper ions, which are lethal to microbes.

Practical experience in the use of high power impulse magnetron sputtering (HiPIMS) technology has revealed that output bias current depends on the total energy output of the cathodes, which means that bias voltage settings do not necessarily match the actual output. In this study, we investigated the effects of bias current and voltage on the characteristics of titanium nitride thin films produced using high impulse magnetron sputtering. The bias current and voltage values were adjusted by varying the supplied cathode power and substrate bias under DC and pulsed-DC output models. Our results revealed that pulse delay (PD) and feed forward (FF) settings can be used to control bias current and voltage. Increasing the bias current from 0.56 to 0.84 was shown to alter the preferred orientation from (111) to (220), increase the deposition rate, and lead to a corresponding increase in film thickness. The surface morphology of all titanium nitride samples exhibited tapered planes attributable to the low bias current and voltage (−30 V). The maximum hardness values were as follows: DC mode (23 GPa) and pulsed-DC mode (19 GPa). The lower hardness values of pulsed-DC samples can be attributed to residual stress, preferred orientation, and surface morphology. The surface of the samples was shown to be hydrophobic, with contact angles of &gt, 100°.

This study deposited CrAlN coatings from Al50Cr50 targets using high-power impulse magnetron sputtering, with a focus on the effects of nitrogen content and substrate bias voltage on the deposition rate, microstructure, crystal orientation, residual stress, and mechanical properties of the coating. The nitrogen content was adjusted by varying the N2/Ar flow ratio between 20% and 140%. Increasing the nitrogen flow rate during deposition led to corresponding decreases in the deposition rate and film thickness. X-ray diffractometer (XRD) analysis revealed that a low N2/Ar flow ratio (&lt, 40%) resulted in amorphous CrAlN, whereas a higher ratio (&gt, 40%) resulted in an face-centered cubic (FCC) phase. Bias voltage also had considerable influence on the residual stress and grain size. A refined grain structure and high internal stress resulted in hard CrAlN coatings. Among the various parameter combinations evaluated in this study, the highest hardness (35.4 GPa) and highest elastic modulus (426 GPa) were obtained using an N2/Ar flow ratio of 100% and a bias voltage of −120 V.

A contemporary hole injection bilayer structure (HIBL) based on molybdenum trioxide (MoO3)-doped N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) has been demonstrated and compared with several efficient transition metal oxide (TMO)-based hole injection layers (HILs). Device performances of OLEDs was significantly improved by the utilization of this HIBL. Results of electroluminescence (EL) spectra, hole-only current density-voltage test and capacitance measurement by impedance spectroscopy (IS) are indicative of enhanced hole injection and transport characteristics. Moreover, ultraviolet photoelectron spectroscopy (UPS) results authenticated a cascading highest occupied molecular orbital (HOMO) energy level contributed to both improved hole injection and transport properties, therefore leads to better carrier balance and device efficiency in OLEDs.

All inorganic perovskite quantum dots (PQDs) and perovskite CsPbX3/SiO2 nanocomposites (PNCs) have shown their potentials for optical and lighting applications. We demonstrate a one-step approach to synthesize PQDs and PNCs more simply and effectively at room temperature in the open air. The resulting PNCs can show a narrow emission in the PL spectra and high stability under ambient conditions. In particular, both green CsPbBr3/SiO2 and red CsPbI3-xBrx/SiO2 PNCs can be obtained by employing this easy and low-cost method. Even, the SiO2 protection can also effectively prevent the halide exchange reaction between green and red PNCs, meaning the capability for white light applications. The resulting white light-emitting diodes (WLEDs) based on the green and red PNCs coated on the blue LED have a white Commission Internationale del’ Enclairage (CIE) coordinates of (0.375, 0.362) and a low correlated color temperature (CCT) of 4054 K.

High-precision trajectory control is considered as an important factor in the performance of industrial two-axis contour motion systems. This research presents an adaptive direct fuzzy cerebellar model articulation controller (CMAC) sliding mode control (DFCMACSMC) for the precise control of the industrial XY-axis motion system. The FCMAC was utilized to approximate an ideal controller, and the weights of FCMAC were on-line tuned by the derived adaptive law based on the Lyapunov criterion. With this derivation in mind, the asymptotic stability of the developed motion system could be guaranteed. The two-axis stage system was experimentally investigated using four contours, namely, circle, bowknot, heart, and star reference contours. The experimental results indicate that the proposed DFCMACSMC method achieved the improved tracking capability, and so reveal that the DFCMACSMC scheme outperformed other schemes of the model uncertainties and cross-coupling interference.

This paper reports on a novel HiPIMS-assisted CAE deposition process using a Ti target for the fabrication of TiN coatings on WC substrates. Our primary objective was to elucidate the influence of duty cycle on the microstructure and mechanical properties of the TiN coatings. Optical images revealed that decreasing the duty cycle led to a corresponding decrease in the number and size of surface macro-particles. A duty cycle of 3% was shown to maximize the flux of ion bombardment, which in turn maximized the number of nanocrystals, while minimizing the size of grains and columnar crystals. The resulting coating presented outstanding hardness (33.6 GPa), elastic modulus (507 GPa), and wear rate 3.32 (10−6 × mm3N−1m−1).

In this study, five AlTiCrN nitride coatings were deposited via high-power impulse magnetron sputtering (HiPIMS). The AlTiCrN coatings were synthesized with high contents of Al or Ti and a lower fraction of Cr, using Ti and Al70Cr30 targets with five different input power ratios. Electron probe microanalyzer results revealed that the increased rate of Ti contents in the coatings can be divided into two regions due to the difference of power densities for HiPIMS (&gt, 0.5 kW/cm2) and modulated pulsed power (MPP) (&lt, 0.5 kW/cm2). The deposition rate and thickness of the coatings depended on the sputtering yield of two metal targets under HiPIMS and MPP modes. The grain size of the coatings decreased from 60 to 40 nm as the input power ratios of the AlCr/Ti targets decreased due to their lower thickness values and lower Al content. Selected area electron diffraction patterns and X-ray diffraction results revealed that the TiN and AlTiN phases can be found in the coating containing higher Ti content, whereas the AlN, CrN, and AlCrN phases were observed in the coating with a higher Al concentration. Nevertheless, decreasing the concentration of Ti had a detrimental effect on the mechanical properties of AlTiCrN coatings, due to a promotion in grain size and the formation of AlN, which is softer than TiN. It is noticed that our results differed from those in previous reports, in which a grain refinement effect was observed due to increasing Al content. In this work, the effect of processing the parameters of the HiPIMS and MPP power systems on the grain size and the mechanical property of the coating was also discussed.

In this study, lead-free LiNbO3-doped (Na0.535K0.48)NbO3 (NKN) ceramics (NKLxN, x = 0–0.09) were prepared using a conventional mixed oxide method to investigate the effects of LiNbO3 additives on the microstructure and electrical properties. The addition of LiNbO3 reduced the optimal sintering temperature from 1100 to 950 ℃ and increased the bulk relative density to 99.61% (g/cm3) at x = 0.05 through the formation of a homogeneous microstructure. The electrical properties remained highly stable, even when the ambient temperature was increased from room temperature to 140 ℃. NKLxN ceramics sintered at 950 ℃ with x = 0.05 exhibited the following excellent piezoelectric properties: kp：50% (34%); kt：53% (40%); Qm：168 (112); d33：150 pC/N (80 pC/N); and tan δ ：4% (8%). These values far exceed those of pure NKN ceramics sintered at 1100 ℃. Surface acoustic wave (SAW) devices fabricated using the proposed NKLxN (x = 0.05) ceramics presented high phase velocity of 3210 m/s, k2 of 6.7%, and TCF of approximately −282 ppm/℃. Our results clearly demonstrate the effectiveness of adding LiNbO3 to prevent deliquescence and thereby enhance resistance to the effects of humidity. The resulting devices are highly sensitive to changes in temperature, making them ideally suited to electromechanical transducers as well as SAW temperature sensors.

In this paper, a single-step chemical bath deposition method was developed for the growth of novel aluminium (Al)-doped zinc oxide nanostructures (NSs) comprising a dual-layer of nanorods/nanowalls. This particular mesoporous structure can accommodate a larger number of ChOx molecules than is possible in a traditional nanorod array. The formation of this dual-layer of NSs depends largely on the content of Al ions and reaction time. A cholesterol biosensor was constructed using these NSs as supporting materials for cholesterol oxidase loading. The device achieved sensitivity of $93.82\mu \text{A}/\text{mMcm}^2$ within a linear-range of 1.3–13 mM.

In this study, the performances of red CsPbI3-based all-inorganic perovskite quantum-dot light-emitting diodes (IPQLEDs) employing polymeric crystalline Poly(3-hexylthiophene-2,5-diyl) (P3HT), poly(9-vinycarbazole) (PVK), Poly(N,N′-bis-4-butylphenyl-N,N′-bisphenyl)benzidine (Poly-TPD) and 9,9-Bis[4-[(4-ethenylphenyl)methoxy]phenyl]-N2,N7-di-1-naphthalenyl-N2,N7-diphenyl-9H-fluorene-2,7-diamine (VB-FNPD) as the hole transporting layers (HTLs) have been demonstrated. The purpose of this work is an attempt to promote the development of device structures and hole transporting materials for the CsPbI3-based IPQLEDs via a comparative study of different HTLs. A full-coverage quantum dot (QD) film without the aggregation can be obtained by coating it with VB-FNPD, and thus, the best external quantum efficiency (EQE) of 7.28% was achieved in the VB-FNPD device. We also reported a standing method to further improve the degree of VB-FNPD polymerization, resulting in the improved device performance, with the EQE of 8.64%.

Transparent conducting Nb-doped titanium oxide (NTO) films were deposited on a non-alkali glass substrate using an RF magnetron sputtering method with post-annealing. Structural, electrical and optical properties of the NTO films were found to be strongly dependent on film thickness. A resistivity of 4.2 × 10−3 Ω cm and an average visible transmittance of ∼70% were obtained at the film thickness of 360 nm, indicating that the polycrystalline NTO fabricated by the sputtering method has sufficient potential as a transparent conducting oxide (TCO) candidate for practical applications.

This paper reports on the fabrication of ZnO nanowalls for use as an electron collecting layer (ECL) in CH3NH3PbI3 perovskite solar cells (PSCs). Two-dimension ZnO nanowalls were grown using a low-temperature chemical bath method with a thin Al film as a seed layer. We compared electron collecting layers based on nanowalls and sol–gel derived ZnO thin film in PSCs and sought to identify the mechanism underlying the collection of electrons. The proposed ZnO nanowalls achieved a fill factor significantly higher than that of ZnO thin films, which translated into a remarkable improvement in power conversion efficiency, reaching 13.6% under AM 1.5G illumination.

This paper reports a novel method for the synthesis of ZnO nanorods, nanowalls, and nanorod/wall structures directly on a substrate, using a simple chemical bath deposition process. The morphology of the resulting structures can be altered simply by adjusting the thickness of an Al thin film, which is used as a doping source. Transmission electron microscopy (TEM) and selected area electron diffraction (SAED) measurements revealed that the resulting ZnO formations possess a wurtzite structure. Inductively coupled plasma mass spectrometry (ICP-MS) revealed that the Al doping of the nanostructures is between 2.1 at% and 4.9 at%. The predominance of violet-blue emissions in the CL spectra of Al-doped and undoped ZnO indicates the presence of interstitial zinc (Zn i ) and zinc vacancies (V Zn ). In this study, the work function was adjusted between 3.81 and 4.39 eV simply by varying the thickness of the Al reaction source.

This study developed a hybrid nanostructure comprising zinc oxide (ZnO) nanorods and aluminium doped ZnO (AZO) nanowalls using a chemical bath deposition method for use in near-ultraviolet (NUV) photosensors. We report on a means of tuning the morphology of ZnO nanostructure using Al thin film as a doping source. An increase in the thickness of the Al thin film causes the evolution of the morphology from nanorods to nanowalls. X-ray photoelectron spectroscopy (XPS) data indicate an increase in the concentration of Al doping from 0 to 9.59 wt.%. Transmission electron microscopy indicates that the ZnO nanorods are single-crystal formations whereas the AZO nanowalls are composed of numerous single-crystal grains. UV–vis absorption spectra revealed a new area of absorption resulting from the AZO nanostructure. The resulting photosensor was tested using a 405 nm light-emitting diode (LED) at a voltage bias of 1 V across the device, wherein a photocurrent-to-dark-current ratio of 99.5 was observed. Our results demonstrate that the low-temperature fabrication of near-UV photosensors using a novel structure comprising nanorods and nanowalls is a feasible and effective approach.

This paper reports on a solvothermal method used in the fabrication of vertically aligned two-dimensional (2D) ZnO nanowall networks and one-dimensional (1D) ZnO nanorods with overlapping structures. The introduction of an Al thin film as a doping source was shown to alter the morphology from rods to walls. The proposed multilayer buffer results in the formation of two types of nanostructure (nanowalls and rods) and also increased the length to which the nanorods grow at the same time. Analysis based on transmission electron microscopy (TEM) and selected area electron diffraction (SAED) led us to formulate a possible growth mechanism and elucidate the optical properties of the ZnO nanostructures.

Superimposed high-power impulse magnetron sputtering (HiPIMS) refers to the insertion of medium frequency (MF) pulses during the off-time of the pulse sequence to enhance the rate of thin film deposition. In this work, we investigated the effects of inserting MF pulses (0 to 42) on the deposition rate, microstructure, and mechanical properties of AlTiN films. Our results indicate that the current-voltage (I-V) characteristics discharging with an Al65Ti35 target were affected by the introduction of N2 reaction gas and the additional MF power output, due to an impedance change under given plasma conditions. All samples presented mixed phases of AlN and TiN based on the chemical composition and crystallographic analysis. Superimposition improved the power-normalized deposition rate from 0.034 to 0.149 nm/min.kW without a significant decline in the adhesion quality of the deposited films. Increasing the number of inserted MF pulses from 0 to 42 led to a decrease in the peak power density of HiPIMS from 1357 to 509 W/cm2 and MF from 115 to 60 W/cm2. This can be attributed to the fact that the configuration of the HiPIMS system in this study used only one DC power supply, which outputted HiPIMS and MF modes together. Increasing the number of inserted MF pulses decreased the hardness of the thin film from 23 to 15 GPa as well as the compressive stress, due to an increase in the average size of the columnar crystals. These findings demonstrate that the application of AlTiN films can greatly enhance the corrosion resistance of SUS304.

In this study, AlCrN films were deposited from Al70Cr30 alloy targets by high-power impulse magnetron sputtering (HiPIMS). The structural characteristics of the AlCrN films were modulated by performing deposition under various N2/Ar flow ratios. The results indicated that increasing the nitrogen content during deposition leads to corresponding decreases in deposition rate and film thickness, as well as a structural transformation from amorphous to crystalline. A mixture of cubic and hexagonal AlCrN phases was found in the films. Three regions of hardness were observed, and hardness increased with increasing N2/Ar ratio and peaked at 33.6GPa. Good adhesion and wear resistance were observed in all samples.

This study developed a hydrothermal method for the growth of three types of zinc oxide (ZnO) nanostructures: nanorods, nanowalls and nanoflowers. The structures are produced at high densities with a high degree of uniformity on Al-coated SiO2 substrates without the need for surfactant. Unlike the random distribution of ZnO nanoflowers reported in previous studies, the proposed method makes it possible to control the distribution of these structures along the grooves created by altering the growth rate of ZnO nanorods and nanowalls. The number of ZnO nanoflowers created in this manner depends on the concentration of solution (HMT: hexamethylenetetramine) and reaction time. Measurements of cathodoluminescence (CL), X-ray diffractometry (XRD), and SEM-EDS confirm that the resulting structures are pure ZnO with good crystallinity. We also investigated the optical properties of these ZnO nanostructures and propose a possible growth mechanism.

In this study, a hybrid nanostructure comprising ZnO nanorods embedded in polymethylmethacrylate (PMMA) was developed for use as an antireflection (AR) coating. The fabrication process includes the etching of PMMA as an alternative to conventional photolithographic methods. This approach enables rapid, large-scale production at low cost with minimal pollution. The PMMA serves to protect the ZnO nanorods against external damage, while the O2 plasma treatment provides a modified surface profile to reduce reflectance. X-ray diffractometer (XRD) measurements and TEM results confirm that the resulting crystal structures are pure ZnO with good crystallinity. This paper compares three hybrid nanostructures (flat film, columnar, and conical) as antireflective layers. The application of poly-Si solar cells with the proposed AR layer was shown to improve cell efficiency by enhancing short-circuit current density.

The effects of ultraviolet (UV)-ozone treatment on solution-processed amorphous InGaZnO (IGZO) thin-film transistors (TFTs) grown using the sol-gel method are investigated. The UV-ozone-treated TFT devices showed an improved field-effect mobility of 1.52 ${\hbox{cm}}^{2}\cdot{\hbox{V}}^{-1}\cdot{\hbox{s}}^{-1}$ and a subthreshold slope (S) of 0.42 V/dec compared to those of IGZO TFT devices with only thermal annealing (0.75 ${\hbox{cm}}^{2}\cdot{\hbox{V}}^{-1}\cdot{\hbox{s}}^{-1}$ and 0.84 V/dec, respectively). The enhancement of the UV-ozone-treated TFTs is mostly attributed to the increased film packing density, higher Al S/D electrodes adhesion properties, reduced oxygen-related defects, and less electron trapping of the IGZO thin films, which improved the TFT performance and bias stress stability.

This paper examines the corrosion resistance of high-speed steel (HSS) substrates subjected to plasma-nitriding (PN) before being coated with CrN (in a single layer) or CrN/Cr2O3 (in multiple layers). Low-temperature (∼300 °C) nitriding treatment was applied for various durations (1 h, 3 h, and 5 h) with the aim of maximizing the adhesion strength and corrosion resistance of the HSS substrate. The multilayer coatings were applied in various thickness ratios of CrN vs Cr2O3 using high-power impulse magnetron sputtering (HiPIMS). The purpose of this study was to investigate the influence of plasma nitriding and Cr-based coating layers on the microstructural characteristics as well as the adhesion and corrosion characteristics. Specimens that underwent PN treatment for 5 h presented Lc1 and Lc2 values of 40.2 N and 78.9 N, respectively. The adhesion strength of the CrN/Cr2O3 multilayer coated PN-HSS substrate (PN-5h) (Lc 1 = 93.8 N) greatly exceeded that of the CrN-coated specimens. These results demonstrate that plasma nitriding and the modulation period strongly affect the adhesion strength between Cr-based coatings and the underlying HSS substrate. Corrosion resistance was characterized in terms of corrosion current, as follows: CrN/Cr2O3 multilayer > CrN layer > base-HSS. These findings also demonstrate that the application of a CrN/Cr2O3 multilayer coating can greatly enhance the corrosion resistance of HSS.

High-power impulse magnetron sputtering (HiPIMS) is a physical vapor deposition technique, developed specifically for the low-temperature deposition of functional thin films. In this study, a graphite target was used for the deposition of diamond-like carbon (DLC) thin films of high optical transmittance on a quartz glass substrate at 25 °C – 30 °C using HiPIMS in unipolar and bipolar modes. Experiments were conducted to determine the influence of DC input power, deposition time, and bias voltage with a fixed duty cycle on the optical characteristics of the resulting amorphous DLC thin films. During deposition, the current-voltage characteristics of discharge with a graphite target were recorded. The optical characteristics were assessed using a UV/visible light-absorption detector and the structure of the DLC thin films was confirmed by Raman spectroscopy. DLC thin films produced in unipolar mode with deposition time of 1 min presented the highest best transmittance of 86%.

This paper introduces a novel TiAlSiN/CrN multilayer film deposited on substrates of silicon Si (100) or tungsten carbide steel using high-power impulse magnetron sputtering. The authors systematically analyzed the effects of N2/Ar flow ratio on the microstructural and mechanical properties of the thin films using TEM, SEM, XRD, and nanoindentation measurements. SEM images revealed that increasing the N2/Ar flow ratio led to corresponding decreases in the thickness of TiAlSiN/CrN multilayer films (from 1.9 to 0.5 μm) and the bilayer (from 21.5 to 6.6 nm). XRD and TEM analysis revealed that under the same conditions, the structure of a TiAlSiN monolayer transformed from amorphous to crystallite. Thus, increasing the N2/Ar flow ratio from 5% to 80% led to a sharp increase in hardness (from 9.8 to 19.6 GPa) and Young's modulus (from 178 to 245 GPa).This paper introduces a novel TiAlSiN/CrN multilayer film deposited on substrates of silicon Si (100) or tungsten carbide steel using high-power impulse magnetron sputtering. The authors systematically analyzed the effects of N2/Ar flow ratio on the microstructural and mechanical properties of the thin films using TEM, SEM, XRD, and nanoindentation measurements. SEM images revealed that increasing the N2/Ar flow ratio led to corresponding decreases in the thickness of TiAlSiN/CrN multilayer films (from 1.9 to 0.5 μm) and the bilayer (from 21.5 to 6.6 nm). XRD and TEM analysis revealed that under the same conditions, the structure of a TiAlSiN monolayer transformed from amorphous to crystallite. Thus, increasing the N2/Ar flow ratio from 5% to 80% led to a sharp increase in hardness (from 9.8 to 19.6 GPa) and Young's modulus (from 178 to 245 GPa).

The anemone-like ZnO nanostructures have been synthesized by hydrothermal method and were further adsorbed immobilized cholesterol oxidase (ChOx) as a nano-biosensor. In this study, the sensitivity of biosensor were improved by varying the thickness of the ZnO seed layer. The SEM analysis showed changes in thickness of seed layer will not affect the morphologies of anemone-like ZnO nanostructures. The X-ray Diffraction patterns showed that the (002) plane of anemone-like ZnO grown on various thickness of the seed layer was more prouded than other crystal plane. Abioelectrode (ChOx/ZnO/ITO/glass) grown on the 30nm of ZnO seed layer with high sensitivity of 57.533μAmM-1cm-2 (1.488 μA (mg/dl) -1cm-2), a wide sensitive range from 25 to 500 mg/dl. It is concluded that the thinner sputtered ZnO seed layer for growing anemone-like ZnO nanostructure can effectively improve the sensitivity of the ZnO biosensor.

This work describes a bulk acoustic resonator (BAR) based on Pt/L0.06Z0.94O/Pt/Ti/Si structure. The L0.06Z0.94O piezofilms are grown by radio frequency magnetron sputtering system and post-treated with ultraviolet (UV)-ozone illumination. The structural and chemical evolutions through various illumination times of the predominantly c-axis orientation LZO films are investigated. The largest piezoelectric coefficient (14.87 pC/N) of the LZO film is obtained after 120 min UV-ozone illumination, which can be ascribed to better crystallization and fewer oxygen-related defects. Furthermore, we adopt the wet chemical etching method and the lift-off process to pattern the piezofilms and electrodes of the BAR device, respectively. The fabricated resonator exhibits high quality factor (Q = 1112) at ~500 MHz. The experimental results verify the crystallinity and the uniformity of the piezofilms play crucial roles of the BAR devices.

The multi-step resistive switching (RS) behavior of a unipolar Pt/Li0.06Zn0.94O/Pt resistive random access memory (RRAM) device is investigated. It is found that the RRAM device exhibits normal, 2-, 3-, and 4-step RESET behaviors under different compliance currents. The transport mechanism within the device is investigated by means of current-voltage curves, in-situ transmission electron microscopy, and electrochemical impedance spectroscopy. It is shown that the ion transport mechanism is dominated by Ohmic behavior under low electric fields and the Poole-Frenkel emission effect (normal RS behavior) or Li+ ion diffusion (2-, 3-, and 4-step RESET behaviors) under high electric fields.

Chelosterol ZnO biosensors were synthesized by hydrothermal method with predeposited ALD-ZnO seed layers. The ZnO nanostructures were examined by SEM, XRD, AFM, respectively. The XRD is used to analyze the crystal structures of ZnO seed layers that were grown by ALD process, then using SEM and AFM to analysis the surface morphologies of them. Growing of one dimensional ZnO nanostructures on seed layer of 10nm thickness, reveals high sensitivity of 3.15 uA (mg/dl)-1cm-2(121.96 uAmM-1cm-2) and low Km value of 29mM in 25-100mg/dl cholesterol concentration range. The response time could be as low as 10seconds. In the study, it is found that increasing the aspect ratio of ZnO one dimensional nanostructure also increases the sensitivity and expends the linear measureable range of detecting cholesterol in solution. The thickness of seed layer has a significant influence on sensitivity for one dimensional nano ZnO cholesterol biosensor.

Nanostructured ZnO materials have received considerable interest from scientists due to their remarkable performance in electronics, optics and photonics.In recent years, ZnO nanostructures with one-dimensional (1D) and two-dimensional (2D) morphologies, such as nanorods, nanobelts, nanowalls and nanoflowers, have been synthesized. Previous research has suggested that providing multiple types of nanostructures is significantly better than just a single type. In this paper, we used Al layers of various thicknesses as a reaction layer to synthesize an array of vertical nanorods and nanowalls on a ZnO-coated substrate. Previous studies reported that Al undergoes chemical reactions under alkaline conditions in the presence of amines (hexamethylenetetramine: HMTA). Our findings indicate that an increase in the Al3+ ion concentration in the precursor solution leads to a morphological evolution from nanorods to nanowalls. Measurements of cathodoluminescence (CL), X-ray diffractometry (XRD), and SEM-EDS confirm that the resulting structures are pure ZnO with good crystallinity. We also investigated the optical properties of these ZnO nanostructures and propose a possible growth mechanism. Figure 1

Li-doped zinc oxide (L0.03Z0.97O) thin films are deposited onto Pt/Ti/SiO2/Si substrates via the radio frequency magnetron sputtering method. The structure evolution with annealing temperature of the predominantly (002)-oriented Li-doped ZnO (LZO) films after in-situ post-annealing process is determined. The largest values of the piezoelectric coefficient (d33) and the remnant polarization (Pr) (22.85 pm/V and 0.655 μC/cm2, respectively) are obtained for LZO films post-annealed at 600 °C, which can be attributed to the predominant (002)-oriented crystalline structure, the release of intrinsic residual compressive stress, and less non-lattice oxygen.