Preparation and Properties of Cu-Containing High-entropy Alloy Nitride Films by Magnetron Sputtering on Titanium Alloy

Magnetron sputtering deposition with regulated Cu target power was used for depositing Cu-containing high-entropy alloy nitride(Cu-(HEA)N)films on TC4 titanium alloy substrates.The microscopic morphologies,surface compositions,and thicknesses of the films were characterized using SEM+EDS;the anti-corrosion,wear resistance and antibacterial properties of the films in simulated seawater were investigated.The experimental results show that all four Cu-(HEA)N films are uniformly dense and contained nanoparticles.The film with Cu doping come into contact with oxygen in the air to form cuprous oxide.The corrosion resistance of the(HEA)N film without Cu doping on titanium alloy is better than the films with Cu doping.The Cu-(HEA)N film with Cu target power of 16 W shows the best wear resistance and antibacterial performance,which is attributed to the fact that Cu can reduce the coefficient of friction and exacerbate corrosion,and the formation of cuprous oxide has antibacterial properties.The findings of this study provide insights for engineering applications of TC4 in the marine field.

Effect of frequency and pulse-on time of high power impulse magnetron sputtering on deposition rate and morphology of titanium nitride using response surface methodology

Titanium nitride thin films were deposited on silicon by high power impulse magnetron sputtering(HiPIMS)method at different frequencies(162-637 Hz)and pulse-on time(60-322μs).Response surface methodology(RSM)was employed to study the simultaneous effect of frequency and pulse-on time on the current waveforms and the crystallographic orientation,microstructure,and in particular,the deposition rate of titanium nitride at constant time and average power equal to 250 W.The crystallographic structure and morphology of deposited films were analyzed using XRD and FESEM,respectively.It is found that the deposition rate of HiPIMS samples is tremendously dependent on pulse-on time and frequency of pulses where the deposition rate changes from 4.5 to 14.5 nm/min.The regression equations and analyses of variance(ANOVA)reveal that the maximum deposition rate(equal to(17±0.8)nm/min)occurs when the frequency is 537 Hz and pulse-on time is 212μs.The experimental measurement of the deposition rate under this condition gives rise to the deposition rate of 16.7 nm/min that is in good agreement with the predicted value.

Carbon nitride transparent counter electrode prepared by magnetron sputtering for a dye-sensitized solar cell

Carbon nitride(CN_x) films supported on fluorine-doped tin oxide(FTO) glass are prepared by radio frequency magnetron sputtering, in which the film thicknesses are 90-100 nm, and the element components in the CNX films are in the range of x = 0.15-0.25. The as-prepared CN_x is for the first time used as counter electrode for dye-sensitized solar cells(DSSCs), and show a preparation-temperature dependent electrochemical performance. X-ray photoelectron spectroscopy(XPS) demonstrates that there is a higher proportion of sp^2 C=C and sp^3 C-N hybridized bonds in CN_x-500(the sample treated at 500 ℃) than in CNX-RT(the sample without a heat treatment). It is proposed that the sp^2 C=C and sp^3 C-N hybridized bonds in the CN_x films are helpful for improving the electrocatalytic activities in DSSCs. Meanwhile, Raman spectra also prove that CN_x-500 has a relatively high graphitization level that means an increasing electrical conductivity. This further explains why the sample after the heat treatment has a higher electrochemical performance in DSSCs. In addition, the as-prepared CN_x counter electrodes have a good light transmittance in the visible light region. The results are meaningful for developing low-cost metal-free transparent counter electrodes for DSSCs.

La-doped Copper Nitride Films Prepared by Reactive Magnetron Sputtering

Copper nitride film （Cu3N） and La-doped copper nitride films （LaxCu3N） were prepared on glass substrates by reactive magnetron sputtering of a pure Cu and a pure La targets under N2 atmosphere. The results show that La-free film was composed of Cu3N crystallites with anti-ReO3 structure with （111） texture. The formation of the LaxCu3N films is affected strongly by La, and the peak intensity of the preferred crystalline [111]-orientation decreases with increasing the concentration of La. High concentration of La may prevent the formation of the Cu3N from crystallization. Compared with the Cu3N films, the resistivity of the LaxCu3N films have been decreased.

Reactive DC Magnetron Sputtering Deposition of Copper Nitride Thin Film

Copper nitride thin film was deposited on glass substrates by reactive DC （direct current） magnetron sputtering at a 0.5 Pa N2 partial pressure and different substrate temperatures. The as-prepared film, characterized with X-Ray diffraction, atomic force microscopy, and X-ray photoelectron spectroscopy measurements, showed a composed structure of Cu3N crystallites with anti-ReO3 structure and a slight oxidation of the resulted film.The crystal structure and growth rate of Cu3N films were affected strongly by substrate temperature. The preferred crystalline orientation of Cu3N films were （111） and （200） at RT, 100℃. These peaks decayed at 200℃ and 300℃ only Cu （111） peak was noticed. Growth of Cu3N films at 100℃ is the optimum substrate temperature for producing high-quality （111） Cu3N films. The deposition rate of Cu3N films estimated to be in range of 18-30 nm/min increased while the resistivity and the microhardness of Cu3N films decreased when the temperature of glass substrate increased.

Properties of Al-doped Copper Nitride Films Prepared by Reactive Magnetron Sputtering

Cu3N and Al Cu3N films were prepared with reactive magnetron sputtering method. The two films were deposited on glass substrates at 0.8 Pa N2 partial pressure and 100 ℃ substrate temperature by using a pure Cu and AI target, respectively. X-ray diffraction （XRD） measurements show that the un-doped film was composed of Cu3N crystallites with anti-ReO3 structure and adopted [111] preferred orientation. XRD shows that the growth of Al-doped copper nitride films （AlxCu3N） was affected strongly by doping AI, the intensity of [111] peak decreases with increasing the concentration of Al and the high concentration of Al could prevent the Cu3N from crystallization. AFM shows that the surface of AlCu3N film is smoother than that of Cu3N film. Compared with the Cu3N films, the resistivities of the Al-doped copper nitride films （AlxCu3N） have been reduced, and the microhardness has been enhanced.

Structure and Tribology Property of Carbon Nitride Films Deposited by MW-ECR Plasma Enhanced Unbalanced Magnetron Sputtering

Carbon nitride films were deposited by a twinned microwave electron cyclotron resonance （ECR） plasma source enhanced unbalanced magnetron sputtering system. The results indicate that the structure of the films is sensitive to the nitrogen content. The increase in the nitrogen flow ratio leads to an increase in the sp3 content and an improvement of the tribological properties.

Chemical Structure of Carbon Nitride Films Prepared by MW-ECR Plasma Enhanced Magnetron Sputtering

Amorphous carbon nitride thin films were prepared by plasma-enhanced DC magnetron sputtering using twinned microwave electron cyclotron resonance plasma sources. Chemical structure of deposited films was investigated using X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The results indicate that the deposition rate is strongly affected by direct current bias, and the films are mainly composed of a single amorphous carbon nitride phase with N/C ratio close to C3N4, and the bonding is predominantly of C^N type.

Influence of Substrate Temperature and Nitrogen Gas on Zinc Nitride Thin Films Prepared by RF Reactive Sputtering

Zinc nitride （Zn3N2） thin films were prepared by radio frequency （RF） magnetron sputtering on quartz glass at different substrate temperatures.The structure and composition were characterized by X-ray diffraction and Raman-scattering measurements,respectively.The polycrystalline phase Zn3N2 films appeared when the ratio of the N2 partial pressure to the total pressure reached 1/2.The effects of the substrate temperature on the electrical and optical properties of the Zn3N2 films were investigated by Hall measurements and optical transmission spectra.The electrical and optical properties of the films were highly dependent on the substrate temperature.With the substrate temperature increasing from 100 to 300℃,the resistivity of the Zn3N2 films decreased from 0.49 to 0.023Ω·cm,the carrier concentration increased from 2.7×10^16 to 8.2×10^19cm^-3,and the electron mobility decreased from 115 to 32cm^2/（V·s）.The deposited Zn3N2 films were considered to be n-type semiconductors with a direct optical band gap,which was around 1.23eV when the substrate temperature was 200℃.

X-Ray Photoelectron Spectroscopy and Raman Spectroscopy Studies on Thin Carbon Nitride Films Deposited by Reactive RF Magnetron Sputtering

Thin carbon nitride (CNx) films were synthesized on silicon substrates by reactive RF magnetron sputtering of a graphite target in mixed N2/Ar discharges and the N2 gas fraction in the discharge gas, F N, varied from 0.5 to 1.0. The atomic bonding configuration and chemical composition in the CNx films were examined using X-ray photoelectron spectroscopy (XPS) and the degree of structural disorder was studied using Raman spectroscopy. An increase in the nitrogen content in the film from 19 to 26 at% was observed at FN = 0.8 and found to influence the film properties;normality tests suggested that the data obtained at FN = 0.8 are not experimental errors. The interpretation of XPS spectra might not be always straightforward and hence the detailed and quantitative comparison of the XPS data with the information acquired by Raman spectroscopy enabled us to interpret the decomposed peaks in the N 1s and C 1s XPS spectra. Two N 1s XPS peaks at 398.3 and 399.8 eV (peaks N1 and N2, respectively) were assigned to a sum of pyridine-like nitrogen and -C≡N bond, and to a sum of pyrrole-like nitrogen and threefold nitrogen, respectively. Further, the peaks N1 and N2 were found to correlate with C 1s XPS peaks at 288.2 and 286.3 eV, respectively;the peak at 288.2 eV might include a contribution of sp3 carbon.

Friction and Wear Behavior of Modified Layer Prepared on Ti-13Nb-13Zr Alloy by Magnetron Sputtering and Plasma Nitriding

Two kinds nitride modified layers were obtained on Ti-13Nb-13 Zr surface to improve the wear property via magnetron sputtering and plasma nitriding techniques, respectively. The structures of the modified layer and the worn surface after sliding test were characterized using X-ray diffraction（XRD） and scanning electron microscopy（SEM）. The friction and wear behavior of the modified layer against alumina ball was investigated in the absence of lubricant under different loads（1 N and 2 N）. The X-ray diffraction analysis reveals that nitride layer is mainly composed of TiN and Ti2N, while coating film consists of Ti N phase. Friction and wear test indicates that both modified layers can improve the wear resistance compared to untreated Ti-13Nb-13 Zr. Ti N thin film produces very hard surface, but may be easy to cause coating fracture and delamination under high normal load. However, nitride layer exhibits better wear performance. This is attributed to hard compound layer maintained its integrity with the hardened nitrogen diffusion zone during friction and wear process.

Microstructure, Hardness and Corrosion Resistance of ZrN Films Prepared by Inductively Coupled Plasma Enhanced RF Magnetron Sputtering

ZrN fihns were deposited on Si（111） and M2 steel by inductively coupled plasma （ICP）-enhanced RF magnetron sputtering. The effect of ICP power on the microstructure, mechanical properties and corrosion resistance of ZrN films was investigated. When the ICP power is below 300 W, the ZrN films show a columnar structure. With the increase of ICP power, the texture coefficient （To） of the （111） plane, the nanohardness and elastic modulus of the films increase and reach the maximum at a power of 300 W. As the ICP Power exceeds 300 W, the films exhibit a ZrN and ZrNx mixed crystal structure without columnar grain while the nanohardness and elastic modulus of the films decrease. All the ZrN coated samples show a higher corrosion resistance than that of the bare M2 steel substrate in 3.5% NaCl electrolyte. The nanohardness and elastic modulus mostly depend on the crystalline structure and Tc of ZrN（111）.

Thick c-BN films deposited by radio frequency magnetron sputtering in argon/nitrogen gas mixture with additional hydrogen gas

The excellent physical and chemical properties of cubic boron nitride(c-BN) film make it a promising candidate for various industry applications. However, the c-BN film thickness restricts its practical applications in many cases. Thus, it is indispensable to develop an economic, simple and environment-friend way to synthesize high-quality thick, stable c-BN films. High-cubic-content BN films are prepared on silicon(100) substrates by radio frequency(RF) magnetron sputtering from an h-BN target at low substrate temperature. Adhesions of the c-BN films are greatly improved by adding hydrogen to the argon/nitrogen gas mixture, allowing the deposition of a film up to 5-μm thick. The compositions and the microstructure morphologies of the c-BN films grown at different substrate temperatures are systematically investigated with respect to the ratio of Hgas content to total working gas. In addition, a primary mechanism for the deposition of thick c-BN film is proposed.

Formation Conditions of TiN Coatings by Reactive Magnetron Sputtering and Its Characteristics

The TiN coatings on the surfaces of various cemented carbides were performed by use of reactive magnetron sputtering. The highest microhardness which was obtained in our experiment was 49 GPa. The order of effects of deposition parameters is resulted from the L16 experiments according to orthogonal design. The pole density analysis indicated that there were a few of the textureless samples. The crystal orientation of TiN exhibited clear regularity and affected microhardness and other properties of films remarkably. A concept relating to structure factor was proposed. A layer-like structure was found. SAES showed that a transition layer exists between substrate and coating and its thickness is of a micron. The formation mechanism of film was discussed.

Structural and optical analysis of Cr_2N thin films prepared by DC magnetron sputtering

Chromium nitride （Cr2N） thin films were prepared by a DC magnetron sputtering technique. The deposition temperature was raised from 50 to 300℃, and its influence on the film structure and refractive index was investigated. X-ray diffraction analysis shows that the crystalline strucure of the films transforms from the （101） to （002） oriented hexagonal CrzN phase as the increase of substrate tempera- ture above 50℃, and a highly texatred film grows at 100℃. An empirical relation between the crystalline orientation and infrared active modes of the films is obtained, i.e., the Fourier transform infrared （FTIR） spectrum of the film prepared at 50℃ exhibits only A1 （TO） mode. The prominent peak in the FTIR spectra of the film prepared above 50℃is assigned to the E1 （TO） mode and is correlated with the （002） or c-axis oriented hexagonal wurtzite phase of Cr2N. In the surface analysis of atomic force microscopy, a transformation from the featureless surface to columnar-type morphology is observed with the increase of substrate temperature from 50 to 100℃, exhibiting c-axis oriented crystallite growth. A further increase in substrate temperature to 200℃ causes the c-axis crystallites to merge, resulting in the formation of voids. The refractive index （n） of the deposited films is obtained using spectroscopic ellipsometry.

Effects of Power Density and Post Annealing Process on the Microstructure and Wettability of TiO_2 Films Deposited by Mid-frequency Magnetron Reactive Sputtering

The relationship of ＂preparation parameters-microstructures-wettability＂ of TiO2 films was reported. In this work, TiO2 films were deposited onto glass and silicon substrates by using mid-frequency dual magnetron sputtering technique at ambient temperature with various power densities and deposition time. After deposition, the films were heat treated at different annealing temperatures. X-ray diffraction （XRD）, Raman spectroscopy, and field-emission scanning electron microscopy （FE-SEM） were utilized to characterize TiO2 films. The wettability of the films was evaluated by water contact angle measurement. The phase transition temperature of TiO2 films depended on the power density. It was demonstrated that wettability was strongly structure dependent and the film with the thickness of 610 nm （the power density was 2.22 W/cm^2） showed the lowest contact angle （8°）. It can be concluded that smaller crystallite size, the rutile phase with （110） face being parallel to the surface, and tensile stress favored the hydrophilicity of the TiO2 films.

Effects of N_2/O_2 flow rate on the surface properties and biocompatibility of nano-structured TiO_xN_y thin films prepared by high vacuum magnetron sputtering

NiTi shape memory alloys（SMA） have many biomedical applications due to their excellent mechanical and biocompatible properties. However, nickel in the alloy may cause allergic and toxic reactions, which limit some applications. In this work, titanium oxynitride films were deposited on NiTi samples by high vacuum magnetron sputtering for various nitrogen and oxygen gas flow rates. The x-ray diffraction（XRD） and x-ray photoelectron spectroscopy（XPS） results reveal the presence of different phases in the titanium oxynitride thin films. Energy dispersive spectroscopy（EDS） elemental mapping of samples after immersion in simulated body fluids（SBF） shows that Ni is depleted from the surface and cell cultures corroborate the enhanced biocompatibility in vitro.

Characterization of DC magnetron sputtering deposited thin films of TiN for SBN/MgO/TiN/Si structural waveguide

Optimal parameters for depositing Titanium nitride （TIN） thin films by DC reactive magnetron sputtering were determined. TiN thin films were deposited on Si （100） substrates by DC reactive magnetron sputtering, at different temperatures, different electrical current values, and different N2/Ar ratios. Structural characteristics of TiN thin films were measured by X-ray diffraction （XRD）; surface morphology of the thin films was characterized using an atomic force microscope （AFM）. The electric resistivity of the TiN films was measured by a four-point probe. In the result, temperature is 500℃, electrical current value is 1.6 A, pure N2 is the reacting gas, TiN thin film has the preferred （200） orientation, resistance is small enough for its use as bottom electrodes.

Fabrication of GaN films through reactive reconstruction of magnetron sputtered ZnO/Ga_2O_3

A simple and easily operated technique was developed to fabricate GaN films. GaN films possessing hexagonal wurtzite structure were fabricated on Si(111) substrates with ZnO buffer layers through nitriding Ga2O3 films in the tube quartz furnace. ZnO buffer layers and Ga3O3 films were deposited on Si substrates in turn by using radio frequency magnetron sputtering system before the nitriding process. The structure and composition of GaN films were studied by X-ray diffraction, selected area electron diffraction and Fourier transform infrared spectrophotometer. The morphologies of GaN films were studied by scanning electron microscopy. The results show that ZnO buffer layer improves the crystalline quality and the surface morphology of the films relative to the films grown directly on silicon substrates. The measurement result of room-temperature photoluminescence spectrum indicates that the photoluminescence peaks locate at 365 nm and 422 nm.

Phase evolution of tantalum nitride and tantalum carbide films with PBII parameters

Tantalum nitride and tantalum carbide films were fabricated using magnetron sputtering of tantalum followed by nitrogen and carbon plasma-based ion implantation （N-PBII and C-PBII）. The phase evolution and morphology of the films were studied using glancing angle X-ray diffraction （GXRD） and transmission electron microscopy （TEM）. It was found that the main phase in the tantalum nitride films was crystalline TaNo.1 whose grain size increases with increasing implantation voltage and phase content increases with increasing implantation dose. In the tantalum carbide film, the main phase was Ta2C. TaC phase also appeared as the implantation dose increased. XRD results from various glancing angles show that the phases with high nitrogen or carbon content, Ta4N5 and TaC, are present in the surface of the films. X-ray photoelectron spectra （XPS） from the tantalum carbide film reveal that the surface carbon content is higher than that of the inner film.