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1.
Ti-Si-N thin films were deposited on HSS substrates at 560°C using plasmaenhanced chemical vapor deposition. Feed gases used were TiCl 4, SiCl 4, N 2, and H 2. The composition of the films could be controlled well through adjustment of the mixing ratio of the chlorides in the feed gases. The Si content in the film varied in the range of O to 40 at. %. It was jbund that a small addition of Si to a TiN film improved the morphology significantlv, showing dense and glasslike structure. Also a much smootherand more homogeneous interface between thefilm and the substrate was obtained. The Ti-Si- N films containing 10–15 at. % Si showed the maximal microhardness value of about 6350 kgf/mm 2, much higher than that of TiN films. 相似文献
2.
This work highlights optical emission spectroscopy (OES) results used for a better understanding of processes occuring in radiofrequency and microwave plasma enhanced chemical vapor deposition in the Si-C-H-Ar gas system. Optical lines such as Si + and H α (λ = 634.71; 656.29 nm), C 2 (λ = 516.52 nm), CH and SiH (λ = 431.42; 412.80 nm) can be considered as tracers of chemical species in the plasmas. Process parameters (growth rate, composition, residual stresses in the films and gas temperature) have their optical signatures (respectively: Si +, H α lines and rotational G 1Σ +g → B 1Σ +u structure of H 2). 相似文献
3.
Using ionic source assistant, Ti and N co‐doped amorphous C (α‐C:N:Ti) thin films were prepared by pulse cathode arc technique. Microstructure, composition, elemental distribution, morphology, and mechanical properties of α‐C:N:Ti films were investigated in dependence of nitrogen source, pulse frequency, and target current by Raman spectroscopy, X‐ray diffraction, scanning electron microscopy, X‐ray photoelectron spectroscopy, atomic force microscopy, nanoindentation, and surface profilometer. The results show the presence of titanium carbide and nitride in a‐C:N:Ti films. The α‐C:N +:Ti film (6 Hz, 60 A) shows the smaller size and the higher disordering degree of Csp 2 clusters. The α‐C:N +:Ti films present smoother surface and smaller particle size than for α‐C:N 2:Ti films. N ions facilitate the formation of N‐sp 3C bonds in the α‐C:N +:Ti films, and α‐C:N +:Ti (10 Hz, 80 A) film possesses the more graphite‐like N bonds. Higher hardness and lower residual stress present in the α‐C:N 2:Ti (10 Hz, 80 A) film. 相似文献
4.
A kind of photoactive multilayer utrathin films has been fabricated via H-bonding attraction from hydroxyphenyl containing polymers as H-donor and diazoresin (DR) as H-acceptor by means of a self-assembly technique. The layer-by-layer deposition of two components is monitored spectrometrically and shows that the UV-VIS absorbance of the film increases linearly both at 250 nm (absorption of benzene nucleus) and at 383 nm (absorption of diazonium group), which indicates that the fabrication proceeds regularly. The nature of H-bonding between layers was verified by the determination of IR spectra of the film fabricated directly on a CaF 2 wafer. The stability of the films toward polar solvents increases dramatically after UV irradiation of the films. It was confirmed provisionally that the bond nature between the layers of the film changes from H-bonding to covalent bonding under UV irradiation. The photodecomposition of the -N 2+ groups of the film under UV light follows first order reaction kinetics and a mechanism of the photoreaction has been tentatively proposed. 相似文献
5.
Sputtered (Ti,Al)N hard coatings are successfully used for dry high speed cutting. These films show a lower oxidation rate
than TiN or TiC coatings. In our work (Ti,Al)N films were deposited on WC-6%Co substrates at a temperature of 490°C by plasma-assisted
chemical vapour deposition (PACVD) using a gas mixture of TiCl 4/AlCl 3/N 2/Ar/H 2. Investigation of microstructure, crystalline structure and chemical composition was carried out using SEM, WDXS, TEM, AES
and XRD techniques. The chemical composition of the deposited films showed a Al to Ti ratio of 1.33. The film thickness was
5.5 μm. Films showed a fine crystalline size, the metastable fcc crystal structure and a columnar growth. The film surface
was under low compressive stress up to several 100 MPa. For (Ti,Al)N/WC-Co compounds the oxidation behaviour up to 1100°C
(high temperature range) was studied. Therefore, samples were annealed or rapidly heated in air and under high vacuum condition
using the laser shock method. The results show decomposition of the (Ti,Al)N structure to the TiN and the AlN phases at temperature
values above 900°C. Heating in air causes growing of a thin aluminum oxide layer at the film surface, which is a barrier for
further oxygen diffusion to the alumina-film boundary. Additionally, at temperatures above 900°C oxidation of the WC-6%Co
substrate surface was obtained in regions of opened cracks and film delamination. 相似文献
6.
The ion species extracted from transition metal nitride thin films were investigated in order to understand the field evaporation mechanism of nitrogen in atom probe analysis. Nitrides of group IV transition metal, ie, titanium (Ti), zirconium (Zr), and hafnium (Hf) nitrides, were chosen for analysis, owing to their good electrical conductivities. The samples were prepared by sputtering deposition of nitride thin film on a tungsten needle. Measurements were performed at 3 different direct current voltages, and for each voltage, we observed different ion species. For TiN and ZrN, both atomic metal ions and molecular ions were detected and TiN and ZrN tended to evaporate in the form of triple-charged molecular ions. For ZrN, Zr 2+, Zr 3+, ZrN 3+, and (ZrN) 23+ were observed at lower direct current voltages. For a higher tip voltage, N + ions were detected in addition to these ions. These results suggest that the evaporation field of nitrogen is higher than those of Zr 3+ and (ZrN) 23+. In the analysis of an HfN tip, no ions could be detected. These results can be explained in terms of the differences between evaporation fields that were roughly estimated from the work functions and the bond energies of the analyzed nitrides. 相似文献
7.
The redox reaction between TiCl 3 and NaNO 3 to form Ti(IV) and NO 2? prior to deposition in a specially designed TiCl 3 + NaNO 3 solution is the key step effectively promoting the cathodic deposition of porous TiO 2 films. The continuous reduction of NO 2? to N 2 and NH 3 generates extensive OH ?, enhancing the deposition rate of TiO 2. The linear sweep voltammetric (LSV) and electrochemical quartz crystal microbalance (EQCM) studies reveal the electrocatalytic effect of oxy-hydroxyl-titanium already deposited onto the substrate for the NO 2? and N 2 reduction. The porous and crystalline structures of as-deposited and annealed TiO 2 films are examined by field-emission scanning electron microscopic (FE-SEM), transmission electron microscopic (TEM) and selected area electron diffraction (SAED) analyses. 相似文献
8.
Homogeneous titanium nitride (TiN) thin film was produced by simple electrophoreic deposition process on Ti substrate in an aqueous suspension of nanosized TiN powder. Nitrogen-doped titanium dioxide (TiO 2−xN x) was synthesized by oxidative annealing the resulted TiN thin film in air. Photoelectrochemical measurements demonstrated visible light photoresponse for the electrode of annealed electrophoreic deposited TiN samples. It is found that the synthesized TiO 2−xN x electrode showed higher photo potential under white and visible light illumination than the pure TiO 2 electrode. The photocurrent under visible light illumination was also observed, which increased with the increase of deposition time of TiN thin films. 相似文献
9.
The combined application of optical emission spectroscopy (OES) and kinetic numerical modelling was employed to determine the N 2+(X 2\( \Sigma_{\text{g}}^{ + } \)), N 3+, and N 4+ densities in the post-discharge (pink afterglow; PA) of a nitrogen flowing DC discharge. We measured the relative densities of the N 2(C 3Π u) and N 2+(B 2\( \Sigma_{\text{u}}^{ + } \)) states along the post-discharge region by OES. The density values were attained as functions of the post-discharge residence time. We fitted the experimental densities with densities calculated from a kinetic numerical model developed to calculate the temporal density of several nitrogen species in the nitrogen afterglow. Analysis of the rate balance equations of these ions indicated that these densities can be determined from data generated from both the model and experimental N 2+(B 2\( \Sigma_{\text{u}}^{ + } \)) density. Thus, we determined the ions density profiles in the nitrogen post-discharge and observed that the N 3+ density is dominant in the PA. This is followed by that of the N 2+(X 2\( \Sigma_{\text{g}}^{ + } \)) and N 4+ ions. Such behaviour has been previously reported in a study that employed mass spectrometry to analyse the ions in the PA generated by a nitrogen high-frequency discharge. In our study, the DC discharge was operated at a gas flow rate of 0.9 Slm ?1, a discharge current of 30 mA, and a gas pressure range of 400–700 Pa. 相似文献
10.
The surface morphology, structure and electrical transport properties of the polycrystalline TiN films fabricated using reactive sputtering at different N 2 partial pressures ( PN2) have been investigated systematically. The films grow with the preferred (200) orientation. The room-temperature resistivity first deceases, then slightly increases with the increase of PN2. The minimum room-temperature resistivity is about 1.7 × 10 −3 Ω cm at PN2 = 0.5 Pa. The low temperature conductance mechanism turns from tunneling across the grain boundaries to variable-range hopping as PN2 increases. The decreased density of states at EF with the increase of N vacancies should be the reason for the increased resistivity of the films fabricated at different PN2. 相似文献
11.
In this paper, a three-level coupled rotating electrodes air plasma at atmospheric pressure is developed for evaluation of nitrogen fixation. Factors influencing the NOx production rate and energy cost, including airflow rate, the input H2O concentration, blade numbers at each rotating electrode and rotating speed, are examined. Air flow rates prove to have no effect on the rotational temperature of N2 337.1 nm and the emission intensities of N2+ and N2, but specific energy input (SEI) and species’ residence time can be shorter with higher air flow rates, resulting in lower NOx concentration and energy cost. The addition of H2O also has a positive effect on both NOx concentration and energy cost. Optical emission spectrum (OES) shows that air?+?H2O plasma has stronger 336 nm (NH) and 309 nm (OH) emission lines than air plasma, suggests NH and OH are the key species in NOx enhancement. The most energy efficient conditions are found at airflow rate of 15 l min?1, 12% H2O concentration, with 4 blades on each rotating speed. Under these conditions, the lowest energy cost is observed to be 165 GJ/tN. 相似文献
12.
In-situ X-ray fluorescence (XRF) analysis has been used to control the deposition process of Ti-N films on steel substrates during reactive sputtering. The analysis system consisted of a tungsten X-ray tube, secondary targets of Cu, Fe and Cr and a Si (Li) detector. The sputtering off the Ti target has been determined indirectly by plasma monitoring using optical emissions spetroscopy (OES) of the Ti atoms, and the film growth has been measured directly by XRF analysis of the surface mass of Ti atoms deposited on the substrate. For zero bias voltage and varying N 2 flow the increment of surface mass per deposition time has been found to incrase linearly with the intensity of the OES signal of Ti. A negative bias voltage U B100 V changes strongly the growth rate by resputtering effects, especially in the range where stoichiometric TiN is formed. 相似文献
13.
The main aim of this investigation was to prefabricate two-dimensional Ni–W/TiN films on oil-gas X52 steel substrates via pulse electrodeposition (PE). The influences of the TiN content in the bath on the surface morphology, nano-hardness, wear, and corrosion properties of the films were also discussed. The results indicated that the TiN particle size was only ~33 nm in 8 g/L TiN electrolyte, which was ~2.4 times less than that of TiN in 16 g/L solution. The Ni–W/8TiN film exhibited a uniform, smooth surface, and the depression depth and protrusion height were 45.3 nm and 81.7 nm, respectively. Three diffraction peaks at 43.72, 50.78, and 75.26° in the Ni–W/4TiN film emerged as the sharpest and narrowest peaks among the four films. Three XPS peaks for the Ni 2p 3/2 were present at 852.13, 856.35, and 861.87 eV in the Ni–W/8TiN film, corresponding to Ni, Ni 2+ (Ni(OH) 2), Ni 3+ (NiOOH) species. Besides, the XPS peak of W 4f 7/2, which located at 33.85 eV belonged to elemental W. The Ni–W/8TiN film had the lowest wear depth and width at 32.1 μm and 5.7 mm, respectively. Only some narrow and shallow scratches were found on the Ni–W/8TiN film surface, showing its outstanding tribological properties among the films tested. In addition, the Ni–W/4TiN film showed the highest mean frictional coefficient of 0.73, which was ~1.6 times more than that of the Ni–W/8TiN film. 相似文献
14.
Because of their outstanding characteristics, diamond‐like carbon (DLC) thin films have been recognized as interesting materials for a variety of applications. For this reason, the effects of the incorporation of different elements on their fundamental properties have been the focus of many studies. In this work, nitrogen‐incorporated DLC films were deposited on Si (100) substrates by DC magnetron sputtering of a graphite target under a variable N 2 gas flow rate in CH 4 + N 2 + Ar gas mixtures. The influence of high N 2 flow ratios (20, 40 and 60%) on the chemical, structural and morphological properties of N‐DLC films was investigated. Different techniques including field emission gun‐equipped scanning electron microscope (FEG‐SEM), energy‐dispersive X‐ray spectroscopy (EDS), atomic force microscopy (AFM), profilometry, Rutherford backscattering spectrometry (RBS) and Raman spectroscopy (325‐nm and 514‐nm excitation) were used to examine the properties of the N‐DLC films. Thus, the incorporation of nitrogen was correlated with the morphology, roughness, thickness, structure and chemical bonding of the films. Overall, the results obtained indicate that the fundamental properties of N‐DLC films are not only related to the nitrogen content in the film but also to the type of chemical bonds formed. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
15.
The deposition of diamondlike carbon (DLC) film and the measurements of ionic species by means of mass spectrometry were carried out in a CH 4/N 2 RF (13.56 MHz) plasma at 0.1 Torr. The film deposition rate greatly depended on both CH 4/N 2 composition ratio and RF power input. It was decreased monotonically as CH 4 content decreased in the plasma and then rapidly diminished to negligible amounts at a critical CH 4 content, which became large for higher RF power. The rate increased with increasing RF power, reaching a maximum value in 40% CH 4 plasma. The predominant ionic products in CH 4/N 2 plasma were NH +
4 and CH 4N + ions, which were produced by reactions of hydrocarbon ions, such as CH +
3, CH +
2, CH +
5, and C 2H +
5 with NH 3 molecules in the plasma. It was speculated that the production of NH +
4 ion induced the decrease of C 2H +
5 ion density in the plasma, which caused a reduction in higher hydrocarbon ions densities and, accordingly, in film deposition rate. The N +
2 ion sputtering also plays a major role in a reduction of film deposition rate for relatively large RF powers. The incorporation of nitrogen atoms into the bonding network of the DLC film deposited was greatly suppressed at present gas pressure conditions. 相似文献
16.
A quantitative analysis is made of the N +2 “2nd negative” emission (“2N”: C 2Σ +u → X 2Σ +g) produced by the impact of 500 eV to 25 keV He + beams on 14N 2, 14N 15N and 15N 2. Above about 5 keV, the relative 2N emission rates from the various vibrational levels of the C state are the same as those observed for ? 2 keV Ne +, or > / 90 eV electron-impact. These limiting distributions are compared to those predicted for a Franck-Condon excitation of the C state, modified by configuration interaction. The weakening in 2N emission at the vibrational levels ν′ > / 3 is ascribed to spontaneous C-state predissociation. The data fully confirm recent reports that this predissociation extends over a wide range of ν′ and that it is subject to a strong isotope effect. The ratios of the rates of C-state predissociation to 2N emission are obtained for the levels ν′ = 3 to 8 of each nitrogen isotope. By means of these data it is shown that near-resonant charge transfer dominates the distribution of vibrational excitation probabilities only at energies below about 10 eV. A comparison is made of absolute cross-sections for C-state emission with those for N + and N +2 production in He +/ 14N 2 collisions at energies between 5.5 eV and 25 keV. 相似文献
17.
Fluorine-doped tin dioxide
(FTO) films were deposited on silicon wafers by inverted pyrosol technique
using solutions with different doping concentration (F/Sn=0.00, 0.12, 0.75
and 2.50). The physical and electrical properties of the deposited films were
analyzed by SEM, XRF, resistivity measurement by four-point-probe method and
Hall coefficient measurement by van der Pauw method. The electrical properties
showed that the FTO film deposited using the solution with F/Sn=0.75 gave
a lowest resistivity of 3.2·10 –4 ohm
cm. The FTO films were analyzed by temperature programmed desorption (TPD).
Evolved gases from the heated specimens were detected using a quadruple mass
analyzer for mass fragments m/z, 1(H +),
2(H 2
+), 12(C +),
14(N +), 15(CH 3
+),
16(O +), 17(OH + or NH 3
+),
18(H 2O + or NH 4
+),
19(F +), 20(HF +), 28(CO +
or N 2
+), 32(O 2
+),
37(NH 4F +), 44(CO 2
+),
120(Sn +), 136(SnO +)
and 152(SnO 2
+). The majority
of evolved gases from all FTO films were water vapor, carbon monoxide and
carbon dioxide. Fluorine ( m/z 19) was detected
only in doped films and its intensity was very strong for highly-doped films
at temperature above 400°C. 相似文献
18.
Nanocrystalline tantalum nitride (TaN) thin films have been deposited by reactive direct current magnetron sputtering technique on Si/SiO 2 (100) substrate with nitrogen flow rate ranging from 0, 3, 5, 7, 9 to 11 standard cubic centimeter per minute (sccm). Structural properties, surface morphology, chemical composition and and resistivity of the TaN films were investigated by X‐ray diffraction (XRD), field emission scanning electron microscopy, X‐ray photoemission spectroscopy (XPS) and four‐point probe measurements, respectively. In the XRD spectra, a classical formation sequence of tantalum nitride phases in the order of Ta‐Ta 2N‐TaN‐Ta 4N 5 and decreasing amount of metallic Ta were observed with increasing nitrogen flow. The electrical resistivity of the TaN film was found to increase with increasing N/Ta ratio as a result of the increased electron scattering from interstitial N atoms. In the XPS analysis, two groups of Ta4f doublets relating to different TaN phases were observed in the core level spectra of TaN films. No strong coupling was observed between the Ta4f doublets and the Ta4p and the N1s groups. The appropriate nitrogen flow was believed to be helpful in the bonding and formation of stoichiometric TaN. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
19.
Aluminum oxynitride films were deposited by ion beam sputtering technique at room temperature. The optical properties and morphologies of the aluminum oxynitride films were studied and reported previously. It was found that the optical properties are closely related to the O contents in the films. In this study, the structures of the films were investigated by X‐ray diffractometer and XPS. Three oxidation states of N 1s in oxynitride films, N +, N 2+ and N 3+, were clearly deduced from N 1s spectra in the amorphous films fabricated under various oxygen partial pressures ( PO2). To our knowledge, three oxidation states of N 1s have not been simultaneously observed and reported in the aluminum oxynitride films previously. Corresponding bonding variations in Al 2p and O 1s spectra indicated more oxygen in oxynitride in the film as PO2 increases. Three aluminum oxynitride networks, AlO 2N, AlO 2.5N and AlO 3N were deduced. Optical properties of aluminum oxynitride films resemble those of AlN and Al 2O 3 films when PO2 is low and high during the deposition. The refractive indices and extinction coefficients of the aluminum oxynitride films can be adjusted by using proper PO2 during the film depositions. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
20.
A steady-state and high-flux helicon-wave excited N 2 plasma was used to oxynitride Si substrates for the synthesis of silicon oxynitride (SiON) films. X-ray and ultraviolet photoelectron spectroscopy (XPS and UPS) have been extensively used to characterize surface quality of the SiON films, and it is found that a large amount of nitrogen (N) can be incorporated into the films. The result of XPS depth profiles shows that the N concentration is high near the surface and the oxide/Si interface. In the UPS spectra, absence of the reappearance of surface states suggests a resistance to clustering of the oxynitride layer. The N 2 flux and Ar mixture quantity can facilitate tuning of the dissociation characteristics in N 2 discharge. By modulating the N 2 fractions, the N + density reaches maximum at a N 2/(N 2 + Ar) flow-rate ratio of 0.5, resulting in incorporation of more N atoms into the SiON films. Considering the easy control of N 2 plasma, our work opens up a new avenue for achieving high-yield SiON films at low temperature. 相似文献
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