Effect of Deposition Time on Properties of Ni–Cu Alloy Films Electrodeposited on ITO Coated Glass Substrates

The structural, magnetic, and surface morphological properties of Ni–Cu films electrodeposited on ITO (indium tin oxide) glass substrates at different deposition times ranging between 2 s and 600 s have been investigated. The structure of the films was studied using X-ray Diffraction (XRD). The XRD results showed that all samples have a face-centered cubic (FCC) structure. From the XRD patterns, it was also found that the crystallographic structure of the films strongly depends on the deposition time. Compositional analysis of Ni–Cu films carried out by energy dispersive X-ray spectroscopy (EDX) indicated that the Ni content within the films increases with increasing deposition time and then almost saturates at deposition time of 600 s. The result of the vibrating sample magnetometer (VSM) measurements revealed that the saturation magnetization increases with increasing Ni content within the film. Atomic force microscopy (AFM) was used to study the topographic properties of Ni–Cu films. It was found that the surface roughness of Ni–Cu alloy films increases with increasing deposition time. Furthermore, the surface texture was found to be isotropic for all films grown at different deposition times.     

Microstructural and morphological characterizations of nanocrystalline Ni–Cu–Fe thin films electrodeposited from electrolytes with different Fe ion concentrations

In the current study, ternary Ni–Cu–Fe thin films have been grown from the electrolytes with different Fe ion concentrations onto indium tin oxide coated glass substrates by galvanostatic electrodeposition at ambient temperature. The microstructural, compositional, and morphological properties have been characterized with respect to Fe ion concentration using X-ray diffraction (XRD), energy dispersive X-ray (EDX) spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). EDX results indicated that the Fe content within the films increased and Ni and Cu contents decreased as the Fe ion concentration in the electrolyte was increased. From the XRD analysis, it was observed that the films have two separate, Cu-rich and Ni-rich phases. It was also observed that the phase separation becomes weaker with increasing Fe ion concentration. All of the films have face-centered cubic structure and [111] preferred crystallographic orientation. The texture degree of the Ni-rich (111) phase increased with the Fe ion concentration. SEM and AFM measurements revealed that the surface morphology is considerably affected by the Fe ion concentration. The size of the grains formed on the film surface and the surface roughness decreased as the Fe ion concentration within the electrolyte increased.     

The impact of implantation dose on the characteristics of diluted-magnetic nonpolar GaN:Cu films

Diluted-magnetic nonpolar GaN:Cu films have been fabricated by implanting Cu ions into p-type nonpolar a-plane(112?0) GaN films with a subsequent thermal annealing process. The impact of the implantation dose on the structural, morphological and magnetic characteristics of the samples have been investigated by means of high-resolution X-ray diffraction (HRXRD), atomic force microscopy (AFM), and superconducting quantum interference device (SQUID). The XRD and AFM analyses show that the structural and morphological characteristics of samples deteriorated with the increase of implantation dose. According to the SQUID analysis, obvious room-temperature ferromagnetic properties of samples were detected. Moreover, the saturation magnetization per Cu atom decreased as the implantation dose increased.     

Differences observed in properties of ternary NiCoFe films electrodeposited at low and high pH

Ternary NiCoFe films were potentiostatically electrodeposited from the electrolytes with low (3.0) and high (3.6) pH levels, and differences in their compositional, structural, magnetic and magnetoresistance properties were studied. The compositional analysis demonstrated that the Ni content in the films decreased, and Co and Fe content increased while electrolyte pH was changed from low to high level. The structural analysis of the films was carried out using the X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The XRD data revealed that the films have a strong (111) texture of the face-centred cubic (fcc) structure at low pH, while for the films at high pH a mixture of dominantly fcc and hexagonal closed packed structure was observed. The SEM studies showed that films grown at low pH level had comparatively larger grains than those at high pH. The magnetic characteristics studied by a vibrating sample magnetometer and magnetotransport properties were seen to be changed by the electrolyte pH. However, all films have in-plane magnetic anisotropy. The differences observed in the magnetic and magnetotransport properties were attributed to the microstructural changes caused by the electrolyte pH.     

Evolution of surface roughness parameters and microstructure in two-phase nanocrystalline Co–Cu films electrodeposited onto ITO coated glass substrates at different deposition potentials

In the present research, we have studied the effect of deposition potential on the film composition, structural, and morphological properties of the electrodeposited Co–Cu thin films grown onto indium tin oxide coated glass substrates. For this purpose, the properties of the films were analyzed by means of X-ray diffraction, energy dispersive X-ray spectroscopy (EDX), and atomic force microscopy (AFM) characterization techniques. Structural characterizations showed that all of the Co–Cu films consist of hexagonal close-packed (hcp) Co and face-centered cubic (fcc) Cu phases. The hcp Co (002)/fcc Cu (111) peak intensity ratio was found to increase as the deposition potential decreased towards more negative values. An increase in the Co content in the Co–Cu films was observed as the applied deposition potential was made more negative according to EDX analysis. The decrease of the applied deposition potential towards more negative values also induced a decrease in the average crystallite sizes of both Co and Cu particles. AFM study indicated that a granular structure of the electrodeposited Co–Cu films regardless of deposition potential. As the applied deposition potential was made more negative, the surface roughness and particle size decreased considerably. Besides, two additional roughness parameters, surface kurtosis and the surface skewness were also obtained and discussed by means of the obtained results under the study.     

Arsenic ion implantation induced structural effects in C60 films

C₆₀ films grown on Si (001) by vacuum evaporation were implanted with 100 keV positive arsenic ions to various doses in the range 1 × 10¹³ to 1 × 10¹⁵ ions/cm². The structural properties of the implanted films were studied using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and atomic force microscopy (AFM). XPS results indicate the formation of arsenic buried layer within C₆₀ film leading to the anisotropy stress in the film. XRD results reveal the preferential orientation of the film along the (531) plane on implantation and it can be due to the re-alignment of the grains as evidenced by our AFM measurement. AFM measurements also reveal the reduction in the grain size and the surface roughness on implantation.     

氩气氛下制备的C_(60)薄膜的形貌、结构和光学性质

用原子力显微镜 (AFM)、X射线衍射 (XRD)、红外光谱 (IR)及紫外 可见光谱 (UV/VIS)研究了在氩 (Ar)气氛下制备的C60 薄膜的表面形貌、结构及光吸收特性。发现其UV/VIS的强度和吸收峰位置明显不同于在真空中制备的C60 薄膜。与真空中制备的C60 薄膜比较 ,所研究薄膜的红外谱没有变化 ,但X射线衍射表明其结构从面心立方 (fcc)相变成fcc相与六角密堆(hcp)相的混合相。AFM表明 ,在Ar气氛中制备的C60 薄膜有较大的表面粒子 ,并且表面生长岛更尖锐。这将有利于C60 薄膜的场电子发射。     

Deposition potential dependence of composition, microstructure, and surface morphology of electrodeposited Ni–Cu alloy films

Composition, microstructure, and surface morphology of Ni–Cu alloy films electrodeposited at different deposition potentials have been investigated. The microstructural analysis carried out by using X-ray diffraction (XRD) confirmed that all Ni–Cu films are polycrystalline in nature and possess face-centered cubic structure. XRD analysis also revealed that the (111) peak of the Ni–Cu alloy films splits into two as Cu-rich and Ni-rich peaks and the peak intensities change depending on the deposition potential and hence the film composition. Compositional analysis of Ni–Cu films carried out by energy dispersive X-ray spectroscopy showed that Ni content within the films increases as the deposition potential becomes more negative. The morphological analysis performed by using a scanning electron microscopy and an atomic force microscopy revealed that the surface morphology changes significantly with applied deposition potential. Furthermore, a direct correlation is observed between the surface roughness and lattice strain.     

沉积厚度对L10-FePd颗粒膜结构和磁性能的影响

采用直流磁控溅射法在石英玻璃基片上制备不同厚度的FePd纳米颗粒膜,利用X射线衍射仪、X射线能谱仪、扫描电子显微镜、原子力显微镜和振动样品磁强计表征薄膜的结构和磁性能。结果表明,经过550℃热处理3h后,薄膜的X射线衍射谱中出现(002)超晶格衍射峰,表明薄膜中出现了四方有序结构。随着薄膜厚度的减小其有序化程度增加,在膜厚为47nm时,样品矫顽力达到3.5kOe,剩磁比达到0.94,最大磁能积((BH)_(max))达到17.6 MGOe。FePd薄膜的相转变温度降低,磁性能较好。     

Substrate dependent structural and magnetic properties of pulsed laser deposited Fe3O4 thin films

Nanocrystalline iron oxide thin films have been deposited on various substrates such as quartz, MgO(100), and Si(100) by pulsed laser deposition technique using excimer KrF laser (248 nm). The orientations, crystallite size and lattice parameters were studied using X-ray diffraction. The XRD results show that the films deposited on MgO and Si substrates are highly oriented and show only (400) and (311) reflections respectively. On the other hand, the orientation of the films deposited on quarts substrate changed from (311) to (400) with an increase in the substrate temperature from 400 degrees C to 600 degrees C, indicating thereby that the film growth direction is highly affected with nature of substrate and substrate temperature. The surface morphology of the deposited films was studied using Atomic Force Microscopy (AFM) and spherical ball like regular features of nanometer size grains were obtained. The magnetic properties were studied by Superconducting Quantum Interference Device (SQUID) magnetometer in the magnetic field +/- 6 Tesla. The magnetic field dependent magnetization (M-H) curves of all the Fe3O4 thin films measured at 5 K and 300 K show the ferrimagnetic nature. The electrochemical sensing of dopamine studied for these films shows that the film deposited on MgO substrate can be used as a sensing electrode.     

Influence of implantation energy on the characteristics of Mn-implanted nonpolar a-plane GaN films

Nonpolar GaN:Mn films have been fabricated by implanting Mn-ion into nonpolar a-plane (112?0) GaN films at room temperature. The influence of implantation energy on the structural, morphological and magnetic characteristics of samples have been investigated by means of stopping and range of ions in matter (SRIM) simulation software, high-resolution X-ray diffraction (HRXRD), atomic force microscopy (AFM), and superconducting quantum interference device (SQUID). According to the SQUID analysis, obvious room temperature ferromagnetic properties of samples were detected. Moreover, the implantation energy has little impact on the ferromagnetic properties of samples. The XRD and AFM analyses show that the structural and morphological characteristics of samples were severely deteriorated with the increase of implantation energy.     

Thickness effect on properties of titanium film deposited by d.c. magnetron sputtering and electron beam evaporation techniques

This paper reports effect of thickness on the properties of titanium (Ti) film deposited on Si/SiO₂ (100) substrate using two different methods: d.c. magnetron sputtering and electron beam (e-beam) evaporation technique. The structural and morphological characterization of Ti film were performed using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). XRD pattern revealed that the films deposited using d.c. magnetron sputtering have HCP symmetry with preferred orientation along (002) plane, while those deposited with e-beam evaporation possessed fcc symmetry with preferred orientation along (200) plane. The presence of metallic Ti was also confirmed by XPS analysis. FESEM images depicted that the finite sized grains were uniformly distributed on the surface and AFM micrographs revealed roughness of the film. The electrical resistivity measured using four-point probe showed that the film deposited using d.c. magnetron sputtering has lower resistivity of ～13 μΩcm than the film deposited using e-beam evaporation technique, i.e. ～60 μΩcm. The hardness of Ti films deposited using d.c. magnetron sputtering has lower value (～7·9 GPa) than the film deposited using e-beam technique (～9·4 GPa).     

薄膜厚度和工作压强对室温制备AZO薄膜性能的影响

采用射频磁控溅射法在室温下、普通玻璃基片上制备了AZO透明导电薄膜。用X射线衍射仪、原子力显微镜、紫外-可见分光光度计和四探针测量了不同薄膜厚度和不同工作压强下所得样品的结构、电学和光学性能,结果表明,所制备的AZO薄膜均具有六角纤锌矿结构,沿c轴择优取向生长;在可见光范围内,薄膜平均透过率约为80%;随着薄膜厚度的增加和工作压强的降低,薄膜的电阻率呈下降趋势;得到的薄膜最低方块电阻为7.5Ω/□。     

Properties of electrodeposited Fe–Cu films grown on ITO coated glass substrates at different electrolyte temperatures

In this study, effect of electrolyte temperature on structural and morphological properties of Fe–Cu films electrodeposited on ITO coated glass substrates has been investigated. Structural analysis carried out by using X-ray diffraction indicated that the films consist of a mixture of face-centered cubic (FCC) Cu and body centered cubic (BCC) α-Fe phases. It was found that the crystalline size of both Fe and Cu increases with increasing electrolyte temperature. Compositional analysis performed using energy dispersive X-ray spectroscopy showed that the Cu content within the films enhances with increasing electrolyte temperature. The surface morphology of Fe–Cu films was studied using a scanning electron microscopy (SEM). SEM results indicated that the surface morphology of Fe–Cu films significantly depends on the electrolyte temperature. The investigation of the residual stress in the films indicated that the residual stress for the FCC Cu is tensile in all films regardless of electrolyte temperature, whereas, for the BCC Fe, it depends on the electrolyte temperature. Correlation between the surface morphology and the residual stress is discussed in terms of the obtained results.     

Coordination assisted molecular assemblies of perylene-3,4,9,10-tetracarboxylic acid with copper (II) ion at the air/water interface

Perylene-3,4,9,10-tetracarboxylic acid (PTCA) was found to form stable Langmuir films at the air/water interface through the coordination with Cu(II) ion in the subphase although the compound itself could not form monolayer on a plain water surface. The Langmuir films can be transferred onto solid substrates by a Langmuir–Schaefer (LS) method. Surface pressure–area isotherm and measurement of the UV–Vis and FT-IR spectra of the transferred LS films confirmed the coordination between the carboxylic group and Cu(II) ion in the Langmuir films. Atomic force microscopy (AFM) measurements indicated that the Langmuir film was composed of small nanoparticles with a diameter of several tens of nanometers. X-ray diffraction (XRD) measurement on the transferred LS films revealed that the film formed a clear layer structure with a distance of 3.9 nm, which was in agreement with the height measurement from the AFM.     

Nanogranular Fe-Cu-Ag thin films: structure, microstructure and giant magnetoresistance

Fe(x)Cu(y)Ag(z) granular thin films with several compositions were prepared by dc magnetron sputtering. These films consist of small Fe magnetic particles embedded in a nonmagnetic CuAg matrix. Structure, microstructure, morphology and magnetotransport properties were studied. The compositions of these samples were determined by energy-dispersive X-ray analysis. X-ray diffraction results showed strong Ag(111) peaks and broad Cu(111) peaks in all the samples. The variation of the (111) lattice spacings indicates a partial intermixing of Fe, Cu and Ag atoms. Microstructural studies using transmission electron microscopy (TEM) on a selected sample showed only Ag reflections and no reflection from Cu and Fe. Both XRD and TEM studies did not reveal any diffraction peak due to Fe and Cu for this sample. The fitting of the experimental grain size data obtained from TEM micrograph to the lognormal distribution function has allowed an estimation of the average grain diameter of 3.7 nm. The surface image of the Fe22Ag78 film observed using a scanning electron microscope showed the presence of droplet like Ag particles on the film surface. The Cu substitution results in smooth films without any Ag particles on the surface. Surface morphology by atomic force microscopy shows that the Fe39Cu13Ag48 film has a surface roughness of 0.75 nm. Finally, we have obtained a maximum giant magnetoresistance ratio of 3.2% in these films measured at 300 K for an in-plane magnetic field of 20 kOe.     

Preparation and properties of thin ZnS:Cu films phosphors

Thin films of ZnS and ZnS:Cu were prepared by an original metalorganic chemical vapour deposition (MOCVD) method under atmospheric pressure onto a glass substrate heated up to 230–250 °C. The film thickness varied from 0.6 to 1 μm. The thin films were doped with Cu and Cl by the thermal treatment during 1 h at 600 °C at atmospheric pressure in the blend composed of a ZnS powder with Cu and Cl compounds. These films were used for fabrication of the thin film electroluminescent (TFEL) devices with a conventional double insulating structure. The structural properties were investigated by use of X-ray diffraction (XRD) techniques and atomic force microscopy (AFM). Electroluminescent (EL) spectra, electrical and EL characteristics were investigated. The EL spectra and characteristics as well as structural parameters depend on the growth conditions and significantly modified after the annealing. Blue color emission with brightness of 10 cd m^− 2 under a sine wave excitation at 60 V and 5 kHz was obtained. The degradation behavior of the TFEL devices with ZnS:[Cu, Cl] films fabricated using an original non-vacuum methods of deposition and annealing is the same as that of commercial thin film phosphor.     

Structural,optical and electrical properties of chemically deposited copper selenide films

Stoichiometric and nonstoichiometric thin films of copper selenide have been prepared by chemical bath deposition technique at temperature below 60°C on glass substrate. The effect of nonstoichiometry on the optical, electrical and structural properties of the film was studied. The bandgap energy was observed to increase with the increase in at % of copper in composition. The grain size was also observed to increase with the decrease of at % of copper in composition. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS), absorption spectroscopy, and AFM. The results are discussed and interpreted.     

Influence of deposition potential on the electrodeposited Ternary CoFeCu films

Ternary CoFeCu films, relating their magnetic and magnetoresistance properties with film composition, surface morphology and the corresponding crystal structure, were investigated in terms of different deposition potentials in electrodeposition. The films were grown on polycrystalline titanium substrates. The potentials were obtained from cyclic voltammetry and the current–time transients were also recorded to control the growth of proper films. From the structural analysis by X-ray diffraction, all films had a face-centred cubic structure and the calculated grain size increased with increasing deposition potential. The film compositions by energy dispersive X-ray spectroscopy revealed that the Co, Fe and Cu contents varied and the scanning electron microscope images disclosed that the film morphologies changed as the deposition potential changed. The saturation magnetization was high and coercivity was low at high deposition potential. The easy axis of magnetization was parallel to the film plane for all films. All films showed anisotropic magnetic resistance and their magnitudes were between 3.2 and 3.8 %. The variations in magnetic and magnetoresistive properties related to the microstructure were attributed to the variation of the film contents caused by deposition potential.     

氧化铟薄膜制备及其特性研究

采用射频磁控溅射法在玻璃衬底上制备氧化铟薄膜,通过测试原子力显微镜、X射线衍射、X射线光电子谱、紫外可见分光光度计以及霍尔效应,研究了氧化铟薄膜的结构和光、电特性.实验发现,氧化铟薄膜表面粗糙度随着生长温度的升高而增大.X射线衍射结果表明薄膜为立方结构的多晶体,并且随着生长温度的升高,可以看到氧化铟薄膜的晶粒变大以及半高宽减小,这也说明结晶质量的改善.在可见光范围的透射率超过90%.同时,在氩气氛围下制备的薄膜迁移率最大,其电阻率、霍尔迁移率和电子浓度分别达到了0.31Ω.cm、9.69 cm2/(V.s)和1×1018cm-3.退火处理可以改善氩氧氛围下制备的薄膜的电学性能.