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1.
This paper reports on the preparation and characterization of CrBN nanocomposite coatings for low friction, low wear and high thermostability applications. Sputtered CrBN thin films were prepared in order to obtain a composite structure consisting of hard CrB2 and CrN crystallites as well as hexagonal BN lubricant phase by unbalanced magnetron sputtering (UBM) of a CrB2 target in an Ar/N2 gas discharge. Coatings, with a total thickness of 4.5-5.5 μm, were deposited at 450 °C on silicon single-crystal substrates. A nanocomposite structure was obtained by increasing the nitrogen content of the sputtering gas. The coating microstructure was investigated on selected samples by high-resolution transmission electron microscopy. The films were generally found to consist of crystallites of a 1-4 nm size embedded in amorphous matrix. This crystalline phase was identified by electron diffraction as hexagonal CrB2 for low nitrogen content and cubic CrN for high nitrogen content. In the medium composition range, the structure was amorphous, still keeping the two-phase morphology. The use of high-resolution imaging mode helped to reveal the composition of the amorphous phase which seems predominantly to consist of boron nitride. 相似文献
2.
Cr-Ru alloy coatings with Cr content ranging from 47 to 83 at.% were deposited at 400 °C by direct current magnetron co-sputtering with a Ti interlayer on silicon substrates. With a total input power of 300 W, the Cr content in the Cr-Ru coatings increased linearly with the increasing input power of Cr. The intermetallic compound phase Cr2Ru with columnar structure was identified for the as-deposited Cr56Ru44 and Cr65Ru35 coatings, resulting in an increase of hardness up to 15-16 GPa. To evaluate the performance of Cr-Ru coatings as a protective coating on glass molding dies, the annealing treatment was conducted at 600 °C in a 50 ppm O2-N2 atmosphere. The outward diffusion and preferential oxidization of Cr in the Cr-Ru coatings resulted in the variations of the crystalline structure, chemical composition distribution, and surface hardness after annealing. X-ray diffraction and transmission electron microscopy (TEM) proved that an oxide scale consisting of Cr2O3 formed on the free surface. Scanning electron microscopy and TEM observed the surface morphology and structural variation. The chemical composition depth profiles were analyzed by Auger electron microscopy, verifying the presence of a Cr-depleted zone beneath the oxide scale. The hardness of Cr56Ru44 and Cr65Ru35 coatings decreased to 11-12 GPa after annealing, accompanied by the replacement of the Cr2Ru phase by the Ru phase. 相似文献
3.
Ren-Hung Lee 《Thin solid films》2010,518(24):7267-7270
The effects of C2H2/(C2H2 + N2) ratios on the characteristics of carbon coatings on optical fibers prepared by thermal chemical vapor deposition are investigated. The C2H2/(C2H2 + N2) ratios are set to 60, 70, 80, 90, and 100%. Additionally, the deposition temperature, working pressure, and mass flow rate are 1003 K, 133 kPa, and 40 sccm, respectively. The deposition rate, microstructure, and electrical resistivity of carbon coatings are measured. The low-temperature surface morphology of carbon-coated optical fibers is elucidated. Experimental results indicate that the deposition rate increases with increasing the C2H2/(C2H2 + N2) ratio, and the deposition process is located at a surface controlled regime. As the deposition rate increases, the electrical resistivity of carbon coatings increases, while the ordered degree, nano-crystallite size, and sp2 carbon atoms of the carbon coatings decrease. Additionally, the low-temperature surface morphology of the carbon coatings shows that if the carbon coating thickness is not smaller than 289 nm, decreasing the deposition rate is good for producing hermetic optical fiber coatings. 相似文献
4.
Nine kinds of nanostructured Cr2N/Cu multilayer thin films were deposited by the bipolar asymmetry reactive pulsed DC magnetron sputtering system. The antibacterial tests of coatings with various bilayer periods (Λ) and different Cr2N/Cu thickness ratios were performed to evaluate the bactericidal ability by E. coli, S. aureus and P. aeruginosa, respectively. The Λ value, thickness values of Cr2N to Cu layers significantly affected the bactericidal rates. The 100% bactericidal rates were achieved when the Λ value reached 20 nm. For the same Λ = 12 nm Cr2N/Cu multilayered coatings, the thickness ratio of Cr2N to Cu also showed strong influence on the bactericidal rates. 相似文献
5.
TiAlBN coatings have been deposited by electron beam (EB) evaporation from a single TiAlBN material source onto AISI 316 stainless steel substrates at a temperature of 450 °C and substrate bias of − 100 V. The stoichiometry and nanostructure have been studied by X-ray photoelectron spectroscopy, X-ray diffraction and transmission electron microscopy. The hardness and elastic modulus were determined by nanoindentation. Five coatings have been deposited, three from hot-pressed TiAlBN material and two from hot isostatically pressed (HIPped) material. The coatings deposited from the hot-pressed material exhibited a nanocomposite nc-(Ti,Al)N/a-BN/a-(Ti,Al)B2 structure, the relative phase fraction being consistent with that predicted by the equilibrium Ti-B-N phase diagram. Nanoindentation hardness values were in the range of 22 to 32 GPa. Using the HIPped material, coating (Ti,Al)B0.29N0.46 was found to have a phase composition of 72-79 mol.% nc-(Ti,Al)(N,B)1 − x+ 21-28 mol.% amorphous titanium boride and a hardness of 32 GPa. The second coating, (Ti,Al)B0.66N0.25, was X-ray amorphous with a nitride+boride multiphase composition and a hardness of 26 GPa. The nanostructure and structure-property relationships of all coatings are discussed in detail. Comparisons are made between the single-EB coatings deposited in this work and previously deposited twin-EB coatings. Twin-EB deposition gives rise to lower adatom mobilities, leading to (111) (Ti,Al)N preferential orientation, smaller grain sizes, less dense coatings and lower hardnesses. 相似文献
6.
P.S. Hoffmann N.I. FainerO. Baake M.L. KosinovaY.M. Rumyantsev V.A. TrunovaA. Klein B. PollakowskiB. Beckhoff W. Ensinger 《Thin solid films》2012,520(18):5906-5913
SiCxNy thin films were produced by plasma-enhanced chemical vapor deposition and characterized by ellipsometry, Fourier transform infrared and Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, as well as, by near-edge X-ray absorption fine structure measurements in total-reflection X-ray fluorescence geometry. The temperature of synthesis was varied between 100 °C and 800 °C, the precursors hexamethyldisilazane or hexamethylcyclotrisilazane were used with an addition of N2, He, and NH3, respectively. The composition of the products was determined to be constant in Si with about 20 at.%, whereas the sum of C and N results in 80 at.% (each varying between 20 and 60 at.%). Consequently, it can be stated, that in the produced silicon carbonitride a network of Si is built with SiCSi, SiCCSi, and SiNSi bridges. The comparison of the chemical composition and of the physical properties shows for the samples produced with He or N2, respectively (without NH3) that the refractive index and the absorption coefficient are increasing with an increasing content of carbon in the final formula SiC4 − nNn (with n = 1, 2, or 3). 相似文献
7.
This paper reports on the structure and mechanical properties of ~ 2 μm thick nanocomposite (nc-) Ti(N,C)/amorphous diamond like carbon (a-C:H) coatings deposited on 100Cr6 steel substrates, using low temperature (~ 200 °C) DC reactive magnetron sputtering. The carbon content was varied with acetylene partial pressure in order to obtain single layer coatings with different a-C:H carbon phase fractions. The nanocrystalline Ti(N,C) phase is approximately stoichiometric for all coatings and the a-C:H phase fraction increases from 31 to 47 at.% as the coatings stoichiometry changed from TiC1.34 N0.51 to TiC2.48 N0.48, respectively. TiC1.34 N0.51 coatings showed the highest nanoindentation hardness (H) of ~ 14 GPa and a modulus (Er) of ~ 144 GPa; H reduced to < 6 GPa and Er to < 70 GPa for TiC2.48 N0.48 coatings. nc-Ti(N,C)/a-C:H coatings are promising candidates for applications where better matching of the modulus between a relatively low modulus substrate, hard loading support layer and low modulus-high H/E ratio top layer is required. 相似文献
8.
Synthesis of Al-Cr-O-N thin films in corundum and f.c.c. structure by reactive r.f. magnetron sputtering 总被引:1,自引:0,他引:1
Advanced PVD coatings for metal cutting applications must exhibit a multifunctional property profile including high hardness, chemical inertness and high temperature stability. Recently, ternary Al-Cr-O thin films with mechanical properties similar or superior to conventional aluminium oxide thin films have been suggested as potential materials meeting such demands. These coatings can be deposited at moderate temperatures in PVD processes. In this work, new quaternary Al-Cr-O-N coatings are suggested as alternative for offering thin film materials of high strength, hardness and even toughness. A combinatorial approach to the synthesis of Al-Cr-O-N thin films by means of reactive r.f. magnetron sputtering is presented. A thorough phase analysis of deposited coatings covering a wide range of elemental compositions revealed a well-defined phase transition from a corundum-type α-(Al1 − x,Crx)2 + δ(O1 − y,Ny)3 structure to a CrN-type f.c.c.-(Al1 − x,Crx)1 + θ(O1 − y,Ny) structure as a function of the Al/Cr ratio and the nitrogen gas flow ratio. Detailed results on the coatings composition, constitution and microstructure are discussed compared to ternary Al-Cr-O thin films deposited by reactive r.f. magnetron sputtering under nearly identical conditions. 相似文献
9.
Nanke JiangDaniel G. Georgiev Ting WenAhalapitiya H. Jayatissa 《Thin solid films》2012,520(6):1698-1704
Zinc nitride films were deposited on glass or silicon substrates by reactive magnetron radio frequency sputtering of zinc in either N2-Ar or N2-Ar-O2 ambient. The effects of varying the nitrogen contents and the substrate temperature were investigated. X-ray diffraction data showed that the as-deposited films contain the zinc nitride cubic crystalline phase with a preferred orientation, and Raman scattering measurements revealed ZnN related modes. According to energy-dispersive X-ray spectroscopy analysis, the as-deposited films were nitrogen-rich and contained only a small fraction of oxygen. Hall-effect measurements showed that p-type zinc nitride with carrier concentration of ~ 1019 cm−3, mobility of ~ 101 cm2/Vs, resistivity of ~ 10−2 Ω ∗ cm, was obtained. The photon energy dependence of optical transmittance suggested that the material has an indirect bandgap. 相似文献
10.
Cu3N-WC films were synthesized on an arc ion plated TiNx interlayer by direct current magnetron sputtering. The Cu3N-WC films, composed of columnar WC crystals 3-5 nm in size and amorphous Cu3N phases, were grown using the layer-plus-island mode. Deposition rate of Cu3N-WC films declined from 11.7 to 7.5 nm/min when the WC target power increased from 200 to 400 W because the Cu target was poisoned by the diffusion of WC molecules. Nano-indentation testing results showed that the highest measure of hardness of Cu3N-WC films was up to ∼ 41 GPa and the H3/E?2 value of the Cu3N-WC47.4 was around 0.41 GPa, indicating the excellent plastic deformation resistance of the film. Incorporation of the soft lubricant Cu3N phase and the uniform distribution of WC hard phases resulted in significant improvements in friction coefficient and wear resistance. As such, Cu3N-WC films have a good potential in future wear applications. 相似文献
11.
Strong amorphization of high-entropy AlBCrSiTi nitride film 总被引:1,自引:0,他引:1
Che-Wei Tsai 《Thin solid films》2012,520(7):2613-2618
Amorphous coatings, particular nitride systems, are of interest for numerous practical applications. Nevertheless, at present only a few amorphous nitride coating systems have been considered, the most notably being the (TM, Si)N system (transition metal (TM) = Ti, Zr, W, Mo). The present study provides an alternative approach for producing amorphous nitride films with high thermal stability up to 700 °C for 2 h. Films are deposited from an equimolar AlBCrSiTi target in various argon/nitrogen atmospheres at different substrate temperatures. It is found that above the nitrogen flow ratio (i.e. RN = N2/N2 + Ar) of 28.6% a near equal ratio between target elements and nitrogen is approached, thus indicating the coatings have the chemical formula of (AlBCrSiTi)N. The glancing-angle X-ray diffractometer and transmission electron microscope investigations indicate that the coatings, regardless of nitrogen concentration or deposition temperature (up to 500 °C), are amorphous. Thermal treatment shows that the amorphous structure of this (AlBCrSiTi)N coating is maintained up to 700 °C when annealing for 2 h in vacuum. At annealing temperatures of 800 °C and above, the amorphous films transform into a simple NaCl-type face-centered cubic solid solution. Even after annealing at 1000 °C for 2 h, the grain size is only 2 nm. High entropy effect, large lattice distortion effect, and sluggish diffusion effect are proposed to account for the formation of amorphous nitrides. 相似文献
12.
Ternary Mo–Cu–N coatings with various Cu contents were deposited on Si wafers and AISI 304 substrates by magnetron co-sputtering from two elemental targets of Mo and Cu in Ar–N2 gas mixtures. The influence of copper content was investigated with regard to the microstructure, morphology, and tribological properties of these coatings. The results indicated that the Mo–Cu–N coatings exhibited face-centered-cubic B1-MoN phase structure. No diffraction peaks of Cu phase appeared in the coatings with Cu content below 11 at.%. The copper segregated in the amorphous inter-granular phase in the coatings. Incorporation of Cu into the growing Mo–N coating led to grain refinement. The average friction coefficient of the Mo–Cu–N coatings decreased from 0.40 to 0.21 with increasing Cu content up to 11 at.% due to formation of lubricious oxides of CuMoO4. 相似文献
13.
Cr-C-N coatings with different compositions, i.e. (C + N)/Cr atomic ratios (x) of 0.81-2.77, were deposited using pulsed closed field unbalanced magnetron sputtering by varying the chromium and graphite target powers, the pulse configuration and the ratio of the nitrogen flow rate to the total gas flow rate. Three kinds of nanostructures were identified in the Cr-C-N coatings dependent on the x values: a nano-columnar structure of hexagonal closed-packed (hcp) Cr2(C,N) and face-centered cubic (fcc) Cr(C,N) at x = 0.81 and 1.03 respectively, a nanocomposite structure consisting of nanocrystalline Cr(C,N) embedded in an amorphous C(N) matrix at x = 1.26 and 1.78, and a Cr-containing amorphous C(N) structure at x = 2.77. A maximum hardness of 31.0 GPa and a high H/E ratio of 1.0 have been achieved in the nc-Cr(C,N)/a-C(N) nanocomposite structure at x = 1.26, whereas the coating with a Cr-containing amorphous C(N) structure had a minimum hardness of 10.9 GPa and a low H/E ratio of 0.08 at x = 2.77. The incorporation of carbon into the Cr-N coatings led to a phase transition from hcp-Cr2(C,N) to fcc-Cr(C,N) by the dissolution into the nanocrystallites, and promoted the amorphization of Cr-C-N coatings with the precipitation of amorphous C(N). It was found that a high x value over 1.0 in the Cr-C-N coatings is the composition threshold to the nanostructure transition. 相似文献
14.
Hydrogen-free amorphous silicon nitride (SiNx) films were deposited at room temperature by microwave electron cyclotron resonance plasma-enhanced unbalance magnetron sputtering. Varying the N2 flow rate, SiNx films with different properties were obtained. Characterization by Fourier-transform infrared spectrometry revealed the presence of Si-N and Si-O bonds in the films. Growth rates from 1.0 to 4.8 nm/min were determined by surface profiler. Optical emission spectroscopy showed the N element in plasma mainly existed as N+ species and N2+ species with 2 and 20 sccm N2 flow rate, respectively. With these results, the chemical composition and the mechanical properties of SiNx films strongly depended on the state of N element in plasma, which in turn was controlled by N2 flow rate. Finally, the film deposited with 2 sccm N2 flow rate showed no visible marks after immersed in etchant [6.7% Ce(NH4)2(NO3)6 and 93.3% H2O by weight] for 22 h and wear test for 20 min, respectively. 相似文献
15.
Al-Si-N coatings were deposited on tungsten carbide (WC-Co) and silicon wafer substrates using Cr and AlSi (12 at.% Si) alloy targets using a dual cathode source with short straight-duct filter in the cathode arc evaporation system. Al-Si-N coatings were synthesized under a constant flow of nitrogen, using various substrate bias voltages at a fixed AlSi cathode power. To enhance adhesive strength, the Cr/(CrxAlySiz)N graduated layer between the top coating and the substrate was deposited as a buffer interlayer. The effects of bias voltage on the microstructure, mechanical and wear properties of the Al-Si-N films were investigated. Experimental results reveal that the Al-Si-N coatings exhibited a nanocomposite structure of nano-crystalline h-AlN, amorphous Si3N4 and a small amount of free Si and oxides. It was also observed that the deposition rate of as-deposited films gradually decreased from about 25.1 to 18.8 nm/min when the substrate bias was changed from − 30 to − 150 V. The XRD results revealed that h-AlN preferred orientation changed from (002) to (100) as the bias voltage increased. The maximum hardness of approximately 35 GPa was obtained at the bias voltage of −90 V. Moreover, the grain size was inversely proportional to the hardness of the film. Wear test results reveal that the Al-Si-N film had a lower coefficient of friction, between 0.5 and 0.7, than that 0.7 of the AlN film. 相似文献
16.
Tae Eun HongKi-Yeung Mun Sang-Kyung ChoiJi-Yoon Park Soo-Hyun Kim Taehoon CheonWoo Kyoung Kim Byoung-Yong LimSunjung Kim 《Thin solid films》2012,520(19):6100-6105
Ruthenium (Ru) thin films were grown by atomic layer deposition using IMBCHRu [(η6-1-Isopropyl-4-MethylBenzene)(η4-CycloHexa-1,3-diene)Ruthenium(0)] as a precursor and a nitrogen-hydrogen mixture (N2/H2) plasma as a reactant, at the substrate temperature of 270 °C. In the wide range of the ratios of N2 and total gas flow rates (fN2/N2 + H2) from 0.12 to 0.70, pure Ru films with negligible nitrogen incorporation of 0.5 at.% were obtained, with resistivities ranging from ~ 20 to ~ 30 μΩ cm. A growth rate of 0.057 nm/cycle and negligible incubation cycle for the growth on SiO2 was observed, indicating the fast nucleation of Ru. The Ru films formed polycrystalline and columnar grain structures with a hexagonal-close-packed phase. Its resistivity was dependent on the crystallinity, which could be controlled by varying the deposition parameters such as plasma power and pulsing time. Cu was electroplated on a 10-nm-thick Ru film. Interestingly, it was found that the nitrogen could be incorporated into Ru at a higher reactant gas ratio of 0.86. The N-incorporated Ru film (~ 20 at.% of N) formed a nanocrystalline and non-columnar grain structure with the resistivity of ~ 340 μΩ cm. 相似文献
17.
C. GuarnerosB. Rebollo-Plata R. Lozada-Morales J.E. Espinosa-RosalesJ. Portillo-Moreno O. Zelaya-Angel 《Thin solid films》2012,520(16):5463-5465
By means of electron gun evaporation Ge1 − xSix:N thin films, in the entire range 0 ≤ x ≤ 1, were prepared on Si (100) and glass substrates. The initial vacuum reached was 6.6 × 10− 4 Pa, then a pressure of 2.7 × 10− 2 Pa of high purity N2 was introduced into the chamber. The deposition time was 4 min. Crucible-substrate distance was 18 cm. X-ray diffraction patterns indicate that all the films were amorphous (a-Ge1 − xSix:N). The nitrogen concentration was of the order of 1 at% for all the films. From optical absorption spectra data and by using the Tauc method the energy band gap (Eg) was calculated. The Raman spectra only reveal the presence of SiSi, GeGe, and SiGe bonds. Nevertheless, infrared spectra demonstrate the existence of SiN and GeN bonds. The forbidden energy band gap (Eg) as a function of x in the entire range 0 ≤ x ≤ 1 shows two well defined regions: 0 ≤ x ≤ 0.67 and 0.67 ≤ x ≤ 1, due to two different behaviors of the band gap, where for x > 0.67 exists an abruptly change of Eg(x). In this case Eg(x) versus x is different to the variation of Eg in a-Ge1 − xSix and a-Ge1 − xSix:H. This fact can be related to the formation of Ge3N4 and GeSi2N4 when x ≤ 0.67, and to the formation of Si3N4 and GeSi2N4 for 0.67 ≤ x. 相似文献
18.
New hafnium β-diketonato-silylamide and siloxides namely Hf(thd)2[N(SiMe3)2]2 (1), Hf(thd)2(OSiMe3)2 (2) and Hf(thd)2(OSitBuMe2)2 (3) (thd=2,2,6,6-tetramethyl-3,5-heptanedionate) were investigated as single-source precursors for low-pressure pulsed liquid injection MOCVD of HfSixOy thin films on Si(1 0 0) and R-plane sapphire. Films were characterized by XRD, XPS and AFM. The growth rate increased in order 1>2>3 in agreement with the decreasing precursor thermal stability. The activation energy was ∼80-100 kJ/mol. The as-deposited at 550-800 °C films were essentially amorphous; hafnia reflections appeared after 1 h annealing at 900 °C probably due to phase separation into amorphous Si-rich silicate and crystallized HfO2. The surface of the films showed similar amounts of Hf and Si (∼1:1) and was overstoichiometric in oxygen (ratio O/(Hf+Si) >2). The bulk of the films was Hf-rich (70-85% of Hf/ Hf+Si) and slightly oxygen-deficient. The new complexes are attractive single-source precursors for the deposition of pure and very smooth (Ra∼0.7 nm, <1% relative to thickness) HfSixOy films. Dielectric constant 11.3 and leakage current density 8×10−4 A/cm2 (at −1 V) were measured for a 22 nm thick film. 相似文献
19.
Chromium nitride coatings were deposited by DC and RF reactive magnetron sputtering on AISI 304 stainless steels without substrate heating. A Cr2N phase was formed in the RF sputtered coatings with a low N2 flow content ranging within 30-50%. A NaCl type CrNx phase was obtained by DC magnetron sputtering with different N2 flow contents. The coating hardness increased with the increase of the N2 flow content. When the coatings deposited with the same N2 flow content were compared, the hardness of the RF sputtered CrNx was higher than that of the DC sputtered CrNx, which was mainly due to the distinct difference between the dense structure (RF process) and the porous structure (DC process). The RF sputtered CrNx coatings showed an excellent adhesion strength as compared to the DC sputtered coatings. By selecting the deposition method and optimizing the N2 flow content, CrNx coatings with a preferred microstructure could be obtained, which would be a candidate material for research and applications in nano-science. 相似文献
20.
C.S. Nimisha K. Yellareswar RaoG. Venkatesh G. Mohan RaoN. Munichandraiah 《Thin solid films》2011,519(10):3401-3406
Lithium phosphorus oxynitride (LiPON) thin films as solid electrolytes were prepared by reactive radio frequency (rf) magnetron sputtering from Li3PO4 powder compact target. High deposition rates and ease of manufacturing powder target compared with conventional ceramic Li3PO4 targets offer flexibility in handling and reduce the cost associated. Rf power density varied from 1.7 Wcm− 2 to 3 Wcm− 2 and N2 flow from 10 to 30 sccm for a fixed substrate to target distance of 4 cm for best ionic conductivity. The surface chemical analysis done by X-ray photoelectron spectroscopy showed incorporation of nitrogen into the film as both triply, Nt and doubly, Nd coordinated form. With increased presence of Nt, ionic conductivity of LiPON was found to be increasing. The electrochemical impedance spectroscopy of LiPON films confirmed an ionic conductivity of 1.1 × 10− 6 Scm− 1 for optimum rf power and N2 flow conditions. 相似文献