Effect Of Deposition Temperature Research Articles

Optimization of atomic layer deposition temperature of ZrO2 protective coat for GaInAsP photonic crystal nanolaser sensor

This study examined the effect of atomic layer deposition temperature of a ZrO2 protective coat on GaInAsP semiconductor photonic crystal nanolaser sensors. At low temperatures (around 100 °C), the nonradiative centers at the ZrO2/GaInAsP interfaces were reduced, and the laser operation and refractive index sensing characteristics were stabilized. At high temperatures (around 250 °C), the nonradiative centers increase, which, in turn, improves the ion sensitivity based on surface recombination.

Effect of Deposition Time and Temperature on Structural, Topographic and Optical Properties of Nano (ZnS) Film Prepared by CBD Technique

The research includes the study of the effect of some preparing factors (time of deposition and temperature) on structural, topographic and optical properties of zinc sulfide (ZnS) nanoscale film. Nanofilms prepared by using a chemical bath deposition .The compositional properties included: pictures of X-ray diffraction (XRD), also included the topographic characteristics: pictures of the optical microscope (ORM) and pictures of the atomic force microscope (AFM), while the included optical properties: transmittance, absorption coefficient, the optical energy gap. The results of X-ray examinations (X-ray) to prepare films by (CBD) method have amorphous structure. It has been observed that increasing the time of deposition led to decrease values ​​of the forbidden energy gap, while it was observed that the increase in temperature led to a increase in the values ​​of the forbidden energy gap .

Synchrotron radiation characterization of magnetron sputtered WC-Co thin films on mild steel substrate

Mild steel offers versatile properties at lower costs. This has given the alloy a large application base in the industry. However, the increasing complexity and severity of service environments have shifted the focus of many industries to structure modification techniques, like physical vapor deposition to improve material properties and performance. Synthesis of WC-Co thin films by physical vapor deposition technology has attracted great research interest owing to the outstanding mechanical properties of the material and its potential to be utilized extreme engineering applications such as in wear-resistance, heavy cutting and excavation industries. The growth in the use of WC-Co thin films in the general mechanical industry is however slow due to lack of data on the tribological characteristics of WC-Co coated materials. Control and manipulation of synthesis parameters are of significant concern in order to tailor such material properties and performance. The focus of this paper is to, therefore, investigate the effect of Rf magnetron power and deposition temperature on the structure and sliding wear behavior of WC-Co thin film. The surface morphology and nature were acquired using x-ray photoelectron spectroscopy (XPS) and Grazing Incidence x-ray absorption spectroscopy (GI-XAS). To validate the synchrotron results, additional analysis was acquired from Scanning electron microscopy (SEM), Raman spectroscopy and surface profilometry to predict and point out optimum synthesis parameters for best properties of the film. Finally, the wear performance of the film-substrate system was determined and reported.

Atomic layer deposition and structure optimization of ultrathin Nb2O5 films on carbon nanotubes for high-rate and long-life lithium ion storage

Niobium pentoxides (Nb2O5) as anode materials has attracted tremendous research interest due to its great potential in rate capability and cyclic durability. Nevertheless, the low electrical conductivity and weak structural controllability of Nb2O5 hinders its practical application. Herein, amorphous Nb2O5 thin films are conformally deposited on carbon nanotubes (CNTs) by controlled atomic layer deposition (ALD) and three types of crystalline Nb2O5@CNTs composites are obtained by post-deposition annealing. Moreover, the effects of deposition temperature and annealing temperature on the crystal structure and surface morphology of Nb2O5@CNTs are investigated. Based on these, the electrochemical performances of Nb2O5@CNTs composites as anode materials are compared in lithium half cells. Impressively, ultrathin and uniform Nb2O5 nanocrystal film with hexagonal (TT) phase on CNTs delivers a capacity of 325.1 mAh g−1 at 0.2 A g−1. Even at a high current density of 3 A g−1, a stable capacity of 170 mAh g−1 is still achieved over 4000 cycles. Its high-rate and long-life lithium ion storage is mainly attributed to the synergistic effects of carbon nanotubes, TT-phase Nb2O5, and ultrathin film structure. Therefore, this synthetic strategy facilitates the development of Nb2O5 as anode materials for high-rate and long-life lithium/sodium ion batteries.

Photocatalytic Degradation of Different VOCs in the Gas-Phase over TiO2 Thin Films Prepared by Ultrasonic Spray Pyrolysis

In this study, we deposited TiO2 thin films onto borosilicate glass by ultrasonic spray pyrolysis at 350 and 450 °C. The aim of study is to determine the effect of deposition temperature on photocatalytic activity of TiO2 thin films and to investigate the performance of TiO2 thin films on photocatalytic degradation of methyl tert-butyl ether (MTBE), acetone, acetaldehyde, and heptane as functions of different operating parameters. TiO2 thin films deposited at 350 and 450 °C have a thickness value of 190 and 330 nm, respectively. All as-prepared TiO2 films possess an anatase crystalline structure. According to the X-ray photon spectroscopy (XPS) study, the TiO2 thin film deposited at 350 °C showed a higher amount of oxygen vacancies and hydroxyl groups on the film surface after UV treatment. The aged-TiO2 thin film deposited at 350 °C showed a water contact angle (WCA) value of 0° after 10 min UV irradiation, showing superhydrophilic surface behavior. The TiO2 film deposited at 350 °C exhibited the highest amount of conversion of MTBE (100%). The results also showed that TiO2 films are capable of photocatalytic degradation of MTBE (100%) and acetaldehyde (approx. 80%) in humid air conditions and high airflow rate. The visible-light-activity of TiO2 thin films was tested with 5 ppm MTBE and acetone. TiO2 thin films deposited at 350 °C with a surface area of 600 cm2 showed 60% of MTBE and 33% of acetone degradation under VIS light.

Nickel Texture Adjustment on Si and Ge and Its Impact on Nickel Silicide and Germanide

Nickel silicide offers advantages over cobalt silicide, but comes along with possible elevated p source-drain leakage currents. In this paper, the effect of deposition temperature on the Ni texture on Si and Ge and its correlation to the silicide and germanide texture is studied for a better control of their properties. A shift from fiber texture to epitaxial Ni growth and an impact on the silicide and germanide texture was found.

The influence of columnar microstructure on diffusion reaction between Ti thin films and aluminum nitride ceramics

In this paper, Ti films with certain thickness were deposited on a polished AlN ceramic substrates by direct current magnetron sputtering at room temperature (RT) and 400 °C, respectively. After deposition, the samples were annealed at 600 °C for 1 h in the mixture gases of argon and hydrogen atmosphere. The microstructure of the Ti films and interface reaction products between Ti/AlN were investigated using X-ray diffraction, and transmission electron microscopy. The effects of deposition temperature on the microstructure and grain orientation of Ti films were studied. It is found that the decomposition of AlN would mainly take place at the AlN/Ti interface during the heat-treated process. After annealing, Al and N react with Ti to produce AlTi3N in the film deposited at 400 °C, while TiN0.3 be formed if deposited at RT. The subsequent rolling-contact-fatigue test proved that after annealing at 600 °C for 1 h, the adhesion strength of Ti/AlN interface deposited at 400 °C is superior to that deposited at RT.

Temperature-controlled conversion from Fe–Si particles to integrated Fe–Si/SiO2 core–shell structure particles during fluidised bed chemical vapour deposition

In the synthesis of ferromagnetic/SiO2 core–shell structures, the minimum formation conditions and evolution mechanism are worth investigating. In the present study, to determine the minimum formation temperature of an integrated Fe–Si/SiO2 core–shell structure during chemical vapour deposition in a fluidised bed, the effects of deposition temperature on the structural and magnetic performances of SiO2 insulation coatings on Fe–Si particles were investigated. Thermodynamic calculations and differential scanning calorimetry were used to understand the thermal decomposition of C8H20O4Si. The results of the theoretical and structural studies showed that the minimum deposition temperature of the amorphous SiO2 insulation coating on the Fe–Si particle surface was ~880 K and that the Fe–Si/SiO2 composite structure started to convert into an integrated Fe–Si/SiO2 core–shell structure after the deposition temperature was raised above 920 K. The increase in the thickness of the SiO2 insulation layer due to the increased deposition temperature was studied using X-ray diffraction and scanning electron microscope analyses. The results of X-ray photoelectron spectroscopy showed that four and five types of electronic structures existed in the SiO2 insulation shell for silicon and oxygen, respectively, and that only 32.74 at.% of the oxygen from the Si(OSi)3(OH) group interacted with the Fe–Si alloy surface. The results of the performance test indicated that the integrated Fe–Si/SiO2 core–shell structure led to a substantial enhancement in the electrical resistivity of the particles and reduction in their saturation magnetisation, but hardly affected the coercive force.

Effects of deposition temperature on optical properties of MgF2 over-coated Al mirrors in the VUV**Project supported by the West Light Foundation of the Chinese Academy of Sciences and the National Natural Science Foundation of China (Grant No. 61805247).

Both long-term environmental durability and high reflectance of protected-Al mirrors are of great importance for developing the optical instruments in the vacuum ultraviolet (VUV) applications. In this paper, the dependence of spectral property and environmental durability of MgF2 over-coated Al mirrors using a 3-step method on deposition temperature of the outermost MgF2 layer are investigated in detail. Optics (reflectance), structure (surface morphology and crystalline), and environmental durability (humidity test) are characterized and discussed. The results show that both optical and moisture-resistant properties of MgF2 over-coated Al mirrors are dependent on MgF2 deposition temperature, and the optimal deposition temperature for the outermost MgF2 layer should be between 250 °C and 300 °C for MgF2 over-coated Al mirrors to have both reasonably high reflectance in the VUV spectral range and high moisture resistance for long lifetime applications.

Synthesis of graphene with different layers on paper-like sintered stainless steel fibers and its application as a metal-free catalyst for catalytic wet peroxide oxidation of phenol

Different layers of graphene (Gr) films are prepared on the paper-like sintered stainless steel fibers (PSSF) support with three-dimensional structure by CVD method. The effects of acetylene flow rate, deposition time, and deposition temperature on the properties of PSSF-Gr are investigated by EDS, AFM, SEM, TEM, and Raman spectroscopy, respectively. Then, the catalytic performances of PSSF-Gr with different layers of Gr films as metal-free catalysts for catalytic wet peroxide oxidation (CWPO) of phenol are assessed in the continuous fixed-bed reactor. The catalytic results demonstrate that the PSSF-Gr catalyst with single layer graphene film achieves the best catalytic performance (phenol and TOC removal efficiency reach 99% and 73%, respectively) after continuously operating for 6 h. Under the treatment of the PSSF-Gr catalyst with single-layer graphene, total phenol oxidation and excellent TOC removal (maintain about 71%) have been achieved for the long-term operation (38 h). Moreover, the phenol conversion of blank experiment (without catalyst) and PSSF are around 40%, which are caused by thermal degradation and thus, the excellent catalytic activity of PSSF-Gr is ascribed to graphene. Like other Fenton’s catalysts, the catalytic mechanism of PSSF-Gr catalyst in phenol degradation is also a ·OH mechanism.

Influence of deposition conditions on nanostructured InSe thin films

In this study, nanostructured indium selenide (InSe) thin films were deposited on Indium tin oxide (ITO)-coated glass substrate using electrochemical deposition (ECD) from aqueous solution containing In(SO4)3.H2O and SeO2. The effects of deposition potential (−0.70 to −1.35 V), time (30-3600 s), temperature (25-80 °C) and pH (2.58 for A samples; 2 for B samples and 1.45 for C samples) on growth of the InSe thin films were examined in terms of their structural, morphological and optical properties. X-ray diffraction (XRD) analysis confirmed that the InSe thin films are in polycrystalline structure. It was found that the values of grain size decreased and the full width half maximum (FWHM) values increased with the increasing deposition potential. According to the absorption measurements, optical properties of the thin films varied with changes in deposition conditions. Based on the atomic force microscopy (AFM) and the scanning electron microscopy (SEM) images, surface morphology of the thin films was influenced by deposition potential and pH of the electrolyte, and non-homogeneous depositions distributed across the entire surface were observed. In addition, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and fourier transform infrared spectroscopy (FT-IR) analyses were used to further examine crystal quality, vibration, chemical binding conditions, In/Se orientation and structure of the prepared InSe thin films. When Raman results are examined, the B12 sample shows a more intensity and narrow peak at 248 cm−1. XPS measurements sowed that A6 sample exhibited more growth in low potential for a long time and better film stoichiometry compared to the other three samples. Also, FT-IR studies prove the presence of InSe. According to the results, the film did not form at low temperatures and short times. However, the film formation began with the increasing deposition temperature and time at the low potential value of −0.730 V. But, it is clear that a high quality film can be obtained in cathodic potential with −1.3 V and shorter deposition time with 300 s at room temperature respectively. Overall results showed that the high quality thin films can be obtained by the ECD technique. However, deposition conditions must be sensitively adjusted to control morphology of the electrodeposited nanoparticles.

Effect of deposition temperature on structure and properties of Nd2O3 thin films prepared by magnetron sputtering

Nd2O3 film is a functional film with great potential application value. In this paper, thinNd2O3 film was prepared on the surface of Si substrates using RF magnetron reactive sputtering. Nd2O3 film with different crystal structures were controlled by changing the deposition temperature. The results show that the Nd2O3 film with a cubic structure can be obtained at 150 °C, while a hexagonal structure appears at 250 °C and above. The refractive indices of the cubic and hexagonal Nd2O3 films were 1.736 and 2.130, respectively. Moreover, the principle of the influence of deposition temperature on the refractive index of the film was illustrated. The hardness and the elastic modulus of the cubic Nd2O3 film were 6.3 GPa and 102 GPa, respectively, which are much lower than the 9.9 GPa and 145 GPa of the hexagonal Nd2O3 film. In addition, with a double-sided cubic Nd2O3 film, the maximum transmittance of the diamond film reached 87.54%. The results show that the Nd2O3 film is an anti-reflection film suitable for optical applications.

Effect of deposition temperature and target-substrate distance on the structure, phases, mechanical and tribological properties of multi-layer HA-Ag coatings obtained by RF magnetron sputtering

The effect of variation in the process parameters of target-substrate distance (4 cm, 6 cm and 8 cm) and deposition temperature between room temperature (RT) and 200 °C, on the chemical composition, structure, phases, mechanical and tribological properties of multi-layer hydroxyapatite (HA) – silver coatings deposited by magnetron sputtering was evaluated. Characterization of the films obtained was performed by energy dispersive spectroscopy, micro-Raman spectroscopy, X-ray diffraction, optical microscopy, atomic force microscopy, scanning electron microscopy, nanoindentation and tribological testing. Better control of the chemical composition and phases was found for coatings deposited at 200 °C, with a Ca/P ratio of 1.66 recorded for the system obtained at 4 cm distance from the target. Moreover, the vibration of the OH− group of HA was preferentially observed in coatings deposited at this temperature. Similarly, higher crystallinity was evidenced in comparison to the coatings obtained at room temperature. Similar behaviors were found for the mechanical properties, which for each system, reduced with increased distance, and improved with increased temperature. Again, the highest values were obtained for the coating deposited at 4 cm and 200 °C, which presented hardness of 7 ± 0.4 GPa, elastic modulus of 134 ± 7 GPa, and critical load of 169 ± 5 mN. Conversely, slightly higher friction coefficients and slightly lower wear rates were obtained in the coatings deposited at 200 °C in comparison to those deposited at RT. Delamination was the predominant wear mechanism in the coatings obtained.

Effect of Deposition Temperature on Microstructure and Critical Current Properties of Zr-Doped GdYBCO Superconducting Tapes Made by MOCVD

The effect of deposition temperature on microstructure and pinning properties of Zr-doped (Gd,Y)Ba 2 Cu 3 O x thin film superconducting tapes made by metal organic chemical vapor deposition has been studied. Systematical analysis on numerous transmission electron microscope (TEM) images showed that higher deposition temperature resulted in BaZrO 3 (BZO) columns with larger cross-sectional sizes (more rods being of width above 5 nm); while lower deposition temperature led to thinner (more rods being of widths about 4 nm or less) BZO rods and consequently higher density of them; the deposition temperature had little effect on the lengths and spayed angle of BZO columns. It was found that Zr:(Gd,Y)Ba 2 Cu 3 O x films deposited at different temperatures could be of significant different temperature dependences of in-field critical current densities. The higher-temperature deposited film exhibit better in-field performance at 77 K, while lower-temperature deposited film was of superior high-field performance at low temperatures. Such a temperature dependent critical current behavior has been interpreted by the sizes and densities of BZO rods.

Surface roughness analysis of Cu films deposited on Si substrates: A molecular dynamic analysis

Cu is a promising material to replace Al and Au in integrated circuits and microscale devices because of its low electrical resistivity, high electromigration resistance, and low cost. However, surface roughness affects the contact resistance of these devices, especially when the device is on a microscale or nanoscale. This paper focuses on surface roughness analysis of Cu films deposited on Si substrates by molecular dynamic simulation based on the mechanism of physical vapor deposition. The effects of film thickness, deposition temperature, deposition interval, and reflow temperature on the surface roughness of Cu films are studied in detail. The simulation results show that the surface roughness can be improved by appropriate adjustments of these parameters. They also provide a foundation for further work on the deposition of Cu films on Si substrates.

High mobility and transparent ZTO ETM prepared by RF reactive co-sputtering for perovskite solar cell application

Thin-films of Zinc Tin Oxide (ZTO) with high charge carrier mobility and superior optical transmittance has been prepared by the rf-reactive co-sputtering technique in argon-oxygen (99:01) ambient. These deposited films have been systematically studied to determine the effect of deposition temperature on film structure, composition, and optoelectronic properties. X-ray diffraction (XRD) spectra indicated that the ZTO films remain amorphous even growth temperature increased to 400 °C. The films deposited at room temperature (RT) and 100 °C were slightly tin-rich found in Energy-dispersive X-ray (EDX) spectroscopy compared to the films deposited over 100 °C. It was found that growth temperature played a crucial role in carrier concentration and mobility of the films and such properties are controlled by the grain boundary scattering over the Sn dopant concentration. The transmittance of the films was found above 85% in the visible range regardless of substrate temperature. The complete perovskite solar cell has been numerically analyzed by employing SCAPS-1D software and the effect of ZTO’s optoelectrical properties on cell performance has been revealed.

Hydrogen concentration at a-Si:H/c-Si heterointerfaces—The impact of deposition temperature on passivation performance

We studied the effect of deposition temperature on the hydrogen distribution and the passivation performance of hydrogenated amorphous silicon (a-Si:H) coated crystalline silicon (c-Si) heterojunctions as a model of high efficiency solar cell structures. Nuclear reaction analysis (NRA) was employed to obtain hydrogen depth profiles of the heterojunctions prepared at temperatures from 80 to 180 °C. The implied open circuit voltage (i-VOC) and carrier lifetime monotonically increased with increasing deposition temperature in the as-deposited samples. NRA clarified that the hydrogen concentration (CH) at the a-Si:H/c-Si interface and in the a-Si:H layer decreased with deposition temperature. The hydrogen concentration around the interface was roughly 3 × 1021 cm-3 for the sample deposited at 180 °C. The NRA results are supplemented by optical constants obtained with spectroscopic ellipsometry (SE). At higher growth temperature, larger refractive indices and extinction coefficients were confirmed by SE analysis, suggesting that fewer hydrogen atoms are incorporated into the a-Si:H layers prepared at higher growth temperature. Furthermore, the passivation performance was enhanced by post deposition annealing (PDA) at 200 °C for 30 min. No significant change of the hydrogen distribution and optical constants was observed after PDA, suggesting that improved passivation is due to a local rearrangement of hydrogen at the molecular level that results in enhanced hydrogenation of dangling bonds.

Investigation on the effect of deposition temperature on structural and nanomechanical properties of electron beam evaporated lanthanum zirconate coatings

In the present study, the effect of deposition temperature in the range 773–973 K on structural and nanomechanical properties of lanthanum zirconate (La2Zr2O7) ceramic coatings deposited on Inconel-718 substrates by EB-PVD process has been investigated. X-ray diffraction and Raman spectroscopy were used to understand the structural details of lanthanum zirconate coatings. Structural studies show that the coatings have defect fluorite structure and are textured at the highest deposition temperature of 973 K. Increase in the surface roughness as a result of increased crystallite size was discussed from SEM and AFM analyses. Scratch test showed higher adhesion strength of the coating with the substrate for the film deposited at higher deposition temperature. Nanoindentation studies indicated that higher deposition temperature leads to enhanced indentation hardness and modulus of the coatings. From the nanoindentation results, resistance to plastic deformation and elastic recovery were also determined to explain the suitability of the lanthanum zirconate as a top coat material for thermal barrier coatings.

Influence of electroplating temperature on the characteristic properties of zinc sulphide

The effect of deposition temperature on the material and electronic properties of ZnS layers grown using a two-electrode electroplating configuration was explored and reported. The aqueous electrolyte from which ZnS layers were deposited contains 0.2 M ammonium thiosulphate ((NH4)2S2O3) and 0.2 M zinc sulphate monohydrate (ZnSO4 · H2O). Deposition temperatures of 30 °C, 55 °C and 80 °C were utilised. The electroplated thin-films were deposited on glass/fluorine-doped tin oxide (FTO) substrate and characterised for their structural, optical, morphological, compositional and electrical properties using x-ray diffraction (XRD), UV-Visible spectrophotometer (Optical absorption), Scanning electron microscopy (SEM), energy-dispersive x-ray analysis (EDX), Photoelectrochemical (PEC) cell measurements and DC conductivity measurements techniques. The XRD results indicate that the electroplated ZnS layers at 30 °C are polycrystalline with the dominant orientation along the ZnS(111)C plane. The XRD micrograph shows the presence of ZnO and unreacted Zn diffractions and amorphisation of the ZnS layers after heat treatment. The readings and estimations made from the UV-Visible spectrophotometric data depict a transition from a bandgap of ∼3.6 eV for the ZnS layers grown at 30 °C to ∼3.1 eV for layers grown at 80 °C. The ∼3.6 eV and ∼3.1 eV obtained bandgaps correspond to the bulk bandgaps of ZnS (of ∼3.7 eV) and ZnO (of ∼3.7 eV), respectively. PEC cell measurements show that the grown ZnS layers are n-type and the magnitude of the PEC signal varies with an increase in the deposition temperature. The DC conductivity measurements revealed that the conductivity of the ZnS layers is between (2 and 6) ×10−4 Ω−1 cm−1. There was a gradual increase in the ZnS layer conductivity as the deposition temperature increased.

Ultra-thin hafnium oxide coatings grown by atomic layer deposition: hydrophobicity/hydrophilicity over time

In this work we studied the effects of thickness and deposition temperature on the physico-chemical properties of hafnium oxide layers grown by atomic layer deposition on different glass substrates. In particular, the hydrophobic/hydrophilic character of the deposited film surfaces was followed over time as a function of the deposition parameters, and especially the type of substrate, including Na-Ca-silicate glass, alkali-borosilicate glass, and thin/flexible alkali-free boroaluminosilicate glass. The chemical, structural, and optical properties of the HfO2 thin films were also analyzed in an attempt to link them to the hydrophobic/hydrophilic properties of the films.