Nano-crystalline diamond (NCD) films were deposited on silicon substrates by a microwave plasma enhanced chemical vapor deposition (MPCVD) reactor in C2H5OH/H2 and CH4/H2/O2 systems, respectively, with a constant ...Nano-crystalline diamond (NCD) films were deposited on silicon substrates by a microwave plasma enhanced chemical vapor deposition (MPCVD) reactor in C2H5OH/H2 and CH4/H2/O2 systems, respectively, with a constant ratio of carbon/hydrogen/oxygen. By means of atomic force microscopy (AFM) and X-ray diffraction (XRD), it was shown that the NCD films deposited in the C2H5OH/H2 system possesses more uniform surface than that deposited in the CH4/H2/O2 system. Results from micro-Raman spectroscopy revealed that the quality of the NCD films was different even though the plasmas in the two systems contain exactly the same proportion of elements. In order to explain this phenomenon, the bond energy of forming OH groups, energy distraction in plasma and the deposition process of NCD films were studied. The experimental results and discussion indicate that for a same ratio of carbon/hydrogen/oxygen, the C2H5OH/H2 plasma was beneficial to deposit high quality NCD films with smaller average grain size and lower surface roughness.展开更多
Fe-Cu thin films of 0.2 mum in thickness with different Cu contents wereprepared by using r.f. magnetron sputtering onto glass substrate. The effect of sputteringparameters, including Ar gas pressure and input rf powe...Fe-Cu thin films of 0.2 mum in thickness with different Cu contents wereprepared by using r.f. magnetron sputtering onto glass substrate. The effect of sputteringparameters, including Ar gas pressure and input rf power, on the structure and magnetic propertieswas investigated. It was found that when the power is lower than 70W, the structure of the filmsremained single bcc-Fe phase with Cu solubility of up to 50at. percent. TEM observations for thebcc-Fe phase showed that the grain size was in the nanometer range of less than 20nm. The coercivityof Fe- Cu films was largely affected by not only Ar gas pressure but also rf power, and reachedabout 2.5Oe in the pressure of 0.67-6.67Pa and in the power of less than 100W. In addition,saturation magnetization, with Cu content less than 60at. percent, was about proportional to thecontent of bcc-Fe. When Cu content was at 60at. percent, however, saturation magnetization was muchsmaller than its calculation value.展开更多
Nano-crystalline diamond (NCD) films were prepared on poly-crystalline diamond (PCD) thick flims by the microwave plasma enhanced chemical vapor deposition (MPCVD) method. Free standing PCD thick film (50 mm in...Nano-crystalline diamond (NCD) films were prepared on poly-crystalline diamond (PCD) thick flims by the microwave plasma enhanced chemical vapor deposition (MPCVD) method. Free standing PCD thick film (50 mm in diameter) with a thickness of 413 μm was deposited in CHn/H2 plasma. It was then abraded for 2 hours and finally cut into pieces in a size of 10×10 mm^2 by pulse laser. NCD fihns were deposited on the thick film substrates by introducing a micro-crystalline diamond (MCD) interlayer. Results showed that a higher carbon concentration (5%) and a lower substrate temperature (650℃) were feasible to obtain a highly smooth interlayer, and the appropriate addition of oxygen (2%) into the gas mixture was conducive to obtaining a smooth nano-crystalline diamond film with a tiny grain size.展开更多
From different reports, it (AZO) and indium-doped including usage areas. We nanocrystalline films with is realized that there is a need to consider all sides of aluminum-doped zinc oxide zinc oxide (IZO) thin film...From different reports, it (AZO) and indium-doped including usage areas. We nanocrystalline films with is realized that there is a need to consider all sides of aluminum-doped zinc oxide zinc oxide (IZO) thin films with their optical, luminescence and surface properties establish an assessment to carry out further information to summarize AZO and IZO impact of the layer number.展开更多
Hexagonal nano-crystalline boron carbonitride (h-BCN) films grown on Si (100) substrate have been precisely investigated. The films were synthesized by radio frequency plasma enhanced chemical vapor deposition using t...Hexagonal nano-crystalline boron carbonitride (h-BCN) films grown on Si (100) substrate have been precisely investigated. The films were synthesized by radio frequency plasma enhanced chemical vapor deposition using tris-dimethylamino borane as a single-source molecular precursor. The deposition was performed by setting RF power at 400 - 800 W. The reaction pressure was at 2.6 Pa and the substrate temperature was recorded at 700°C - 800°C. Formation of the nano-crystalline h-BCN compound has been confirmed by X-ray diffraction analysis. The diffraction peaks at 26.3° together with a small unknown peak at 29.2° were elucidated due to the formation of an h-BCN structure. The films composed of B, C, and N atoms with different B-N, B-C, C-N chemical bonds in forming the sp2-BCN atomic configuration studied by X-ray photoelectron spectroscopy. Orientation and local structures of the h-BCN hybrid were studied by near-edge X-ray absorption fine structure (NEXAFS) measurements. The dominant presence of p* and s* resonance peaks of the sp2-hybrid orbitals in the B K-edge NEXAFS spectra revealed the formation of the sp2-BCN configuration around B atoms like-BN3 in h-BN. The orientation was suggested on the basis of the polarization dependence of B K-edge and N K-edge of the NEXAFS spectra.展开更多
In order to investigate nanomechanical properties of nanostructured Ti metallic material, pure Ti films were prepared by magnetron sputtering at the bias voltage of 0-140 V. The microstructure of Ti films was characte...In order to investigate nanomechanical properties of nanostructured Ti metallic material, pure Ti films were prepared by magnetron sputtering at the bias voltage of 0-140 V. The microstructure of Ti films was characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM) and high-resolution transmission electron microscopy(HRTEM). It is interesting to find that the microstructure of pure Ti films was characterized by the composite structure of amorphous-like matrix embodied with nanocrystallines, and the crystallization was improved with the increase of bias voltage. The hardness of Ti films measured by nanoindentation tests shows a linear relationship with grain sizes in the scale of 6-15 nm. However, the pure Ti films exhibit a soft tendency characterized by a smaller slope of Hall-Petch relationship. In addition, the effect of bias voltage on the growth orientation of Ti films was discussed.展开更多
In this paper, diamond-like carbon (DLC) films were deposited on Ti alloy by electro-deposition. DLC films were brown andcomposed of the compact grains whose diameter was about 400 nm. Examined by XPS, the main compos...In this paper, diamond-like carbon (DLC) films were deposited on Ti alloy by electro-deposition. DLC films were brown andcomposed of the compact grains whose diameter was about 400 nm. Examined by XPS, the main composition of the filmswas carbon. In the Raman spectrum, there were a broad peak at 1350 cm^(-1) and a broad peak at 1600 cm^(-1), which indicatedthat the films were DLC films.展开更多
A study was conducted to develop low-friction, wear-resistant surfaces on high temperature alloys for the temperature range from 26℃ to 900℃. The approach investigated consists of modifying the naturally occurring o...A study was conducted to develop low-friction, wear-resistant surfaces on high temperature alloys for the temperature range from 26℃ to 900℃. The approach investigated consists of modifying the naturally occurring oxide film in order to improve its tribological properties. Improvement is needed at low temperatures where the oxide film, previously formed at high temperature, spalls due to stresses induced by sliding. Experiments with Ti, W and Ta additions show a beneficial effect when added to Ni and Ni-base alloys. Low friction can be maintained down to 100℃ from 900℃. For unalloyed Ni friction and surface damage increases at 400℃ to 500℃. Two new alloys were perpared based on the beneficial results of binary alloys and ZrO2 diffusion in Ni.Low friction at temperature above 500℃ and reasonable values (0.32~0.42) at low temperature are obtained.展开更多
The two series of as-deposited and annealed Ti/Co/Ti thin films were deposited by magnetron sputtering onto glass substrates at room temperature. The structural and magnetic properties of the films at room temperature...The two series of as-deposited and annealed Ti/Co/Ti thin films were deposited by magnetron sputtering onto glass substrates at room temperature. The structural and magnetic properties of the films at room temperature were investigated as function of Co layer thickness. X-ray diffraction (XRD) profiles show Co nanograins are formed as the hexagonal-close-packed (hcp) structure. The perpendicular coercivity of the Ti(15 nm)/Co(30 nm)/Ti(15 nm) film annealed at 450 ℃ for 30 min is about 288 kA·m-1.展开更多
Ti33O55 films are deposited with the help of an electron beam evaporator for their applications in metasurfaces. The film of subwavelength (632nm) thickness is deposited on a silicon substrate and annealed at 400℃....Ti33O55 films are deposited with the help of an electron beam evaporator for their applications in metasurfaces. The film of subwavelength (632nm) thickness is deposited on a silicon substrate and annealed at 400℃. The ellipsometry result shows a high refractive index above 2.5 with the minimum absorption coefficient in the visible region, which is necessary for high efficiency of transparent metasurfaces. Atomic force microscopy analysis is employed to measure the roughness of the as-deposited films. It is seen from micrographs that the deposited films are very smooth with the minimum roughness to prevent scattering and absorption losses for metasurface devices. The absence of grains and cracks can be seen by scanning electron microscope analysis, which is favorable for electron beam lithography. Fourier transform infrared spectroscopy reveals the transmission and reflection obtained from the film deposited on glass substrates. The as-deposited film shows high transmission above 60%, which is in good agreement with metasurfaces.展开更多
In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performanc...In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.展开更多
Two types of Sb-doped SnO2 films on titanium substrate were prepared by the combination of electro-deposition and dip-coating (Ti/SnO2-Sb2O4/SnO2-Sb2O4) and single dip-coating (Ti/SnO2-Sb2O4), respectively. The surfac...Two types of Sb-doped SnO2 films on titanium substrate were prepared by the combination of electro-deposition and dip-coating (Ti/SnO2-Sb2O4/SnO2-Sb2O4) and single dip-coating (Ti/SnO2-Sb2O4), respectively. The surface morphology and crystalline structure of both film electrodes were characterized using X-ray diffractometry(XRD) and scanning electron microscopy(SEM). XRD spectra indicate that the rutile SnO2 forms in two films and a TiO2 crystallite exists only in Ti/SnO2-Sb2O4 electrode. SEM images show that the surface morphology of two films is typically cracked-mud structure. The photooxidation experiment was proceeded to further confirm the two electrode activity. The results show that the photoelectrocatalytic degradation efficiency of Ti/SnO2-Sb2O4 electrode with sub-layer is higher than that of simple Ti/SnO2-Sb2O4 electrode using phenol as a model organic pollutant. The Ti/SnO2-Sb2O4/SnO2-Sb2O4 photoanode has a better photoelectrochemical performance than Ti/SnO2-Sb2O4 photoanode for the removal of organic pollutants from water.展开更多
Anodized composite films containing Si C nanoparticles were synthesized on Ti6Al4 V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) ...Anodized composite films containing Si C nanoparticles were synthesized on Ti6Al4 V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray photoelectron spectroscopy(XPS) were employed to characterize the morphology and composition of the films fabricated in the electrolytes with and without addition of Si C nanoparticles. Results show that Si C particles can be successfully incorporated into the oxide film during the anodizing process and preferentially concentrate within internal cavities and micro-cracks. The ball-on-disk sliding tests indicate that Si C-containing oxide films register much lower wear rate than the oxide films without Si C under dry sliding condition. Si C particles are likely to melt and then are oxidized by frictional heat during sliding tests. Potentiodynamic polarization behavior reveals that the anodized alloy with Si C nanoparticles results in a reduction in passive current density to about 1.54×10-8 A/cm2, which is more than two times lower than that of the Ti O2 film(3.73×10-8 A/cm2). The synthesized composite film has good anti-wear and anti-corrosion properties and the growth mechanism of nanocomposite film is also discussed.展开更多
A film growth mechanism, expressed in terms of depositing hard films onto the soft substrate, was proposed. Multicomponent thin films of Ti-Si-N were deposited onto Al substrate with a double-target magnetron sputteri...A film growth mechanism, expressed in terms of depositing hard films onto the soft substrate, was proposed. Multicomponent thin films of Ti-Si-N were deposited onto Al substrate with a double-target magnetron sputtering system in an Ar-N 2 gas mixture. The Ti-Si-N films were investigated by characterization techniques such as X-ray diffraction (XRD), atomic force microscope (AFM), electron probe microanalyzer (EPMA), scratch test and nanoindentation. The as-deposited films have a good adhesion to Al substrate and appear with smooth and lustrous surface. The films show nanocomposite structure with nano TiN grains embedded in an amorphous SiN x matrix. The maximum hardness of the films was achieved as high as 27 GPa. The influences of the N 2 flow rate and substrate temperature on the growth rate and quality of the films were also discussed. For all samples, the Ar flow rate was maintained constant at 10 ml min 1 , while the flow rate of N 2 was varied to analyze the structural changes related to chemical composition and friction coefficient. The low temperature in the deposited Ti-Si-N films favors the formation of crystalline TiN, and it leads to a lower hardness at low N 2 flow rate. At the same time, the thin films deposited are all crystallized well and bonded firmly to Al substrate, with smooth and lustrous appearance and high hardness provided. The results indicate that magnetron sputtering is a promising method to deposit hard films onto soft substrate.展开更多
Bi3.25La0.75Ti3O12(BLT)thin films were prepared on Pt/Ti/SiO2/Si substrate by the sol-gel method.The effect of annealing on their structures and ferroelectric properties was investigated.The XRD patterns indicate th...Bi3.25La0.75Ti3O12(BLT)thin films were prepared on Pt/Ti/SiO2/Si substrate by the sol-gel method.The effect of annealing on their structures and ferroelectric properties was investigated.The XRD patterns indicate that the BLT films annealed at different temperatures are randomly orientated and the single perovskite phase is obtained at 550℃.The remmant polarization increnses and the coercive field decreases with the annealing temperature increasing.The leakage current density of the BLT films annealed at 700℃ is about 5.8×10^-8A/cm^2 at the electrie field of 250kv/cm.展开更多
围绕压阻传感器领域对高性能类金刚石(Diamond Like Carbon,DLC)薄膜压阻敏感材料的需求,针对金属掺杂DLC存在的载流子输运行为和实际多工况(如温度、湿度等)下压阻性能不明的问题,本工作以Ti-石墨复合拼接靶为靶材,采用高功率脉冲磁控...围绕压阻传感器领域对高性能类金刚石(Diamond Like Carbon,DLC)薄膜压阻敏感材料的需求,针对金属掺杂DLC存在的载流子输运行为和实际多工况(如温度、湿度等)下压阻性能不明的问题,本工作以Ti-石墨复合拼接靶为靶材,采用高功率脉冲磁控溅射技术,高通量制备出4种Ti含量(原子分数为0.43%~4.11%)的Ti掺杂类金刚石(Ti-DLC)薄膜,研究了Ti含量对薄膜组分结构、电学性能、变湿度环境下压阻性能的影响规律。结果表明:Ti含量(原子分数)在0.43%~4.11%范围内,掺杂Ti原子均以固溶形式均匀镶嵌于非晶碳网络中,Ti-DLC薄膜电学行为表现为典型半导体特性,在200~350 K温度范围内,薄膜电阻率均随温度升高而降低。载流子传导机制在200~270 K内为Mott型三维变程跳跃传导,在270~350 K范围内则为热激活传导。Ti-DLC薄膜压阻系数(Gauge Factor,GF)最大值为95.1,在20%~80%相对湿度范围内,所有样品GF均随湿度增加而增大,这可能是引入的固溶Ti原子缩短了导电相之间的平均距离,同时吸附表面水分子导致电阻变化。展开更多
Using metallo-organatic compound TPT as the source of Ti, H13 mould steels were coated with Ti(CN) films by plasma-assisted chemical vapor deposition (PCVD) and the properties of Ti(CN) films were studied. Under the a...Using metallo-organatic compound TPT as the source of Ti, H13 mould steels were coated with Ti(CN) films by plasma-assisted chemical vapor deposition (PCVD) and the properties of Ti(CN) films were studied. Under the appropriate temperature and pressure, Ti(CN) films on H13 mould steel surfaces had the highest micro-hardness of HV1760 at 500°C, and the films showed excellent anti-oxidation property below 500°C. The lifetime of Ti(CN)-coated augers and dies could be enhanced 7 and 4 times longer than those of untreated respectively.展开更多
文摘Nano-crystalline diamond (NCD) films were deposited on silicon substrates by a microwave plasma enhanced chemical vapor deposition (MPCVD) reactor in C2H5OH/H2 and CH4/H2/O2 systems, respectively, with a constant ratio of carbon/hydrogen/oxygen. By means of atomic force microscopy (AFM) and X-ray diffraction (XRD), it was shown that the NCD films deposited in the C2H5OH/H2 system possesses more uniform surface than that deposited in the CH4/H2/O2 system. Results from micro-Raman spectroscopy revealed that the quality of the NCD films was different even though the plasmas in the two systems contain exactly the same proportion of elements. In order to explain this phenomenon, the bond energy of forming OH groups, energy distraction in plasma and the deposition process of NCD films were studied. The experimental results and discussion indicate that for a same ratio of carbon/hydrogen/oxygen, the C2H5OH/H2 plasma was beneficial to deposit high quality NCD films with smaller average grain size and lower surface roughness.
基金This research is sponsored by the National Natural Science Foundation of China (Grant No.69971006).
文摘Fe-Cu thin films of 0.2 mum in thickness with different Cu contents wereprepared by using r.f. magnetron sputtering onto glass substrate. The effect of sputteringparameters, including Ar gas pressure and input rf power, on the structure and magnetic propertieswas investigated. It was found that when the power is lower than 70W, the structure of the filmsremained single bcc-Fe phase with Cu solubility of up to 50at. percent. TEM observations for thebcc-Fe phase showed that the grain size was in the nanometer range of less than 20nm. The coercivityof Fe- Cu films was largely affected by not only Ar gas pressure but also rf power, and reachedabout 2.5Oe in the pressure of 0.67-6.67Pa and in the power of less than 100W. In addition,saturation magnetization, with Cu content less than 60at. percent, was about proportional to thecontent of bcc-Fe. When Cu content was at 60at. percent, however, saturation magnetization was muchsmaller than its calculation value.
基金supported by the Research Pund of Hubei Provincial Department of Education of China (No.Q20081505)
文摘Nano-crystalline diamond (NCD) films were prepared on poly-crystalline diamond (PCD) thick flims by the microwave plasma enhanced chemical vapor deposition (MPCVD) method. Free standing PCD thick film (50 mm in diameter) with a thickness of 413 μm was deposited in CHn/H2 plasma. It was then abraded for 2 hours and finally cut into pieces in a size of 10×10 mm^2 by pulse laser. NCD fihns were deposited on the thick film substrates by introducing a micro-crystalline diamond (MCD) interlayer. Results showed that a higher carbon concentration (5%) and a lower substrate temperature (650℃) were feasible to obtain a highly smooth interlayer, and the appropriate addition of oxygen (2%) into the gas mixture was conducive to obtaining a smooth nano-crystalline diamond film with a tiny grain size.
文摘From different reports, it (AZO) and indium-doped including usage areas. We nanocrystalline films with is realized that there is a need to consider all sides of aluminum-doped zinc oxide zinc oxide (IZO) thin films with their optical, luminescence and surface properties establish an assessment to carry out further information to summarize AZO and IZO impact of the layer number.
文摘Hexagonal nano-crystalline boron carbonitride (h-BCN) films grown on Si (100) substrate have been precisely investigated. The films were synthesized by radio frequency plasma enhanced chemical vapor deposition using tris-dimethylamino borane as a single-source molecular precursor. The deposition was performed by setting RF power at 400 - 800 W. The reaction pressure was at 2.6 Pa and the substrate temperature was recorded at 700°C - 800°C. Formation of the nano-crystalline h-BCN compound has been confirmed by X-ray diffraction analysis. The diffraction peaks at 26.3° together with a small unknown peak at 29.2° were elucidated due to the formation of an h-BCN structure. The films composed of B, C, and N atoms with different B-N, B-C, C-N chemical bonds in forming the sp2-BCN atomic configuration studied by X-ray photoelectron spectroscopy. Orientation and local structures of the h-BCN hybrid were studied by near-edge X-ray absorption fine structure (NEXAFS) measurements. The dominant presence of p* and s* resonance peaks of the sp2-hybrid orbitals in the B K-edge NEXAFS spectra revealed the formation of the sp2-BCN configuration around B atoms like-BN3 in h-BN. The orientation was suggested on the basis of the polarization dependence of B K-edge and N K-edge of the NEXAFS spectra.
基金supported by the National Natural Science Foundation of China(Grant No:10274018)the Foundation of Hebei Provincial Education Department(Grant No:002013)the Key Foundation of Hebei Normal University(Grant No:120203).
基金Projects(51102264,51271123)supported by the National Natural Science Foundation of ChinaProjects(5313310202,13ZR1427900)supported by Shanghai Municipal Education Commission,China
文摘In order to investigate nanomechanical properties of nanostructured Ti metallic material, pure Ti films were prepared by magnetron sputtering at the bias voltage of 0-140 V. The microstructure of Ti films was characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM) and high-resolution transmission electron microscopy(HRTEM). It is interesting to find that the microstructure of pure Ti films was characterized by the composite structure of amorphous-like matrix embodied with nanocrystallines, and the crystallization was improved with the increase of bias voltage. The hardness of Ti films measured by nanoindentation tests shows a linear relationship with grain sizes in the scale of 6-15 nm. However, the pure Ti films exhibit a soft tendency characterized by a smaller slope of Hall-Petch relationship. In addition, the effect of bias voltage on the growth orientation of Ti films was discussed.
基金Our work is supported by the Natural Science Fund of Jiangsu Province(BK20001414).
文摘In this paper, diamond-like carbon (DLC) films were deposited on Ti alloy by electro-deposition. DLC films were brown andcomposed of the compact grains whose diameter was about 400 nm. Examined by XPS, the main composition of the filmswas carbon. In the Raman spectrum, there were a broad peak at 1350 cm^(-1) and a broad peak at 1600 cm^(-1), which indicatedthat the films were DLC films.
文摘A study was conducted to develop low-friction, wear-resistant surfaces on high temperature alloys for the temperature range from 26℃ to 900℃. The approach investigated consists of modifying the naturally occurring oxide film in order to improve its tribological properties. Improvement is needed at low temperatures where the oxide film, previously formed at high temperature, spalls due to stresses induced by sliding. Experiments with Ti, W and Ta additions show a beneficial effect when added to Ni and Ni-base alloys. Low friction can be maintained down to 100℃ from 900℃. For unalloyed Ni friction and surface damage increases at 400℃ to 500℃. Two new alloys were perpared based on the beneficial results of binary alloys and ZrO2 diffusion in Ni.Low friction at temperature above 500℃ and reasonable values (0.32~0.42) at low temperature are obtained.
基金This work was financially supported by the National Natural Science Foundation of China (No.10274018) and the Foundation of Hebei Provincial Education Department (No.2002116).
文摘The two series of as-deposited and annealed Ti/Co/Ti thin films were deposited by magnetron sputtering onto glass substrates at room temperature. The structural and magnetic properties of the films at room temperature were investigated as function of Co layer thickness. X-ray diffraction (XRD) profiles show Co nanograins are formed as the hexagonal-close-packed (hcp) structure. The perpendicular coercivity of the Ti(15 nm)/Co(30 nm)/Ti(15 nm) film annealed at 450 ℃ for 30 min is about 288 kA·m-1.
基金supported by the National Natural Science Foundation of China (Nos. 52071278, 51827801)the National Key Research and Development Program of China (No. 2018YFA0703603)。
基金Information Technology University of the Punjab, Lahore, Pakistan for financial supportthe financial support by Engineering Research Center Program(NRF-2015R1A5A1037668)+1 种基金global Ph.D. fellowship(NRF-2016H1A2A1906519)the KRF fellowship(NRF-2017H1D3A1A02011379)through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (MSIP) of Korean government
文摘Ti33O55 films are deposited with the help of an electron beam evaporator for their applications in metasurfaces. The film of subwavelength (632nm) thickness is deposited on a silicon substrate and annealed at 400℃. The ellipsometry result shows a high refractive index above 2.5 with the minimum absorption coefficient in the visible region, which is necessary for high efficiency of transparent metasurfaces. Atomic force microscopy analysis is employed to measure the roughness of the as-deposited films. It is seen from micrographs that the deposited films are very smooth with the minimum roughness to prevent scattering and absorption losses for metasurface devices. The absence of grains and cracks can be seen by scanning electron microscope analysis, which is favorable for electron beam lithography. Fourier transform infrared spectroscopy reveals the transmission and reflection obtained from the film deposited on glass substrates. The as-deposited film shows high transmission above 60%, which is in good agreement with metasurfaces.
文摘In this work, TiO2/Ti composite films were fabricated by 2-setp MCT and the following high temperature oxidation. Antibacterial activity of the composite films treated by ultrasonic cleaning to increase the performance reliability was examined. The prepared TiO2/Ti composite films showed high photocatalytic activity in the degradation of methylene blue solution. It is obvious that? TiO2/Ti composite films have antibacterial activity under UV irradiation.
基金Projects(20476070,20876104) supported by the National Natural Science Foundation of China
文摘Two types of Sb-doped SnO2 films on titanium substrate were prepared by the combination of electro-deposition and dip-coating (Ti/SnO2-Sb2O4/SnO2-Sb2O4) and single dip-coating (Ti/SnO2-Sb2O4), respectively. The surface morphology and crystalline structure of both film electrodes were characterized using X-ray diffractometry(XRD) and scanning electron microscopy(SEM). XRD spectra indicate that the rutile SnO2 forms in two films and a TiO2 crystallite exists only in Ti/SnO2-Sb2O4 electrode. SEM images show that the surface morphology of two films is typically cracked-mud structure. The photooxidation experiment was proceeded to further confirm the two electrode activity. The results show that the photoelectrocatalytic degradation efficiency of Ti/SnO2-Sb2O4 electrode with sub-layer is higher than that of simple Ti/SnO2-Sb2O4 electrode using phenol as a model organic pollutant. The Ti/SnO2-Sb2O4/SnO2-Sb2O4 photoanode has a better photoelectrochemical performance than Ti/SnO2-Sb2O4 photoanode for the removal of organic pollutants from water.
基金Project(51271012)supported by the National Natural Science Foundation of China
文摘Anodized composite films containing Si C nanoparticles were synthesized on Ti6Al4 V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray photoelectron spectroscopy(XPS) were employed to characterize the morphology and composition of the films fabricated in the electrolytes with and without addition of Si C nanoparticles. Results show that Si C particles can be successfully incorporated into the oxide film during the anodizing process and preferentially concentrate within internal cavities and micro-cracks. The ball-on-disk sliding tests indicate that Si C-containing oxide films register much lower wear rate than the oxide films without Si C under dry sliding condition. Si C particles are likely to melt and then are oxidized by frictional heat during sliding tests. Potentiodynamic polarization behavior reveals that the anodized alloy with Si C nanoparticles results in a reduction in passive current density to about 1.54×10-8 A/cm2, which is more than two times lower than that of the Ti O2 film(3.73×10-8 A/cm2). The synthesized composite film has good anti-wear and anti-corrosion properties and the growth mechanism of nanocomposite film is also discussed.
基金supported by the Cultivation Fund of the Key Scientific and Technical Innovation Project and Ministry of Education of China (No. 707015)
文摘A film growth mechanism, expressed in terms of depositing hard films onto the soft substrate, was proposed. Multicomponent thin films of Ti-Si-N were deposited onto Al substrate with a double-target magnetron sputtering system in an Ar-N 2 gas mixture. The Ti-Si-N films were investigated by characterization techniques such as X-ray diffraction (XRD), atomic force microscope (AFM), electron probe microanalyzer (EPMA), scratch test and nanoindentation. The as-deposited films have a good adhesion to Al substrate and appear with smooth and lustrous surface. The films show nanocomposite structure with nano TiN grains embedded in an amorphous SiN x matrix. The maximum hardness of the films was achieved as high as 27 GPa. The influences of the N 2 flow rate and substrate temperature on the growth rate and quality of the films were also discussed. For all samples, the Ar flow rate was maintained constant at 10 ml min 1 , while the flow rate of N 2 was varied to analyze the structural changes related to chemical composition and friction coefficient. The low temperature in the deposited Ti-Si-N films favors the formation of crystalline TiN, and it leads to a lower hardness at low N 2 flow rate. At the same time, the thin films deposited are all crystallized well and bonded firmly to Al substrate, with smooth and lustrous appearance and high hardness provided. The results indicate that magnetron sputtering is a promising method to deposit hard films onto soft substrate.
文摘Bi3.25La0.75Ti3O12(BLT)thin films were prepared on Pt/Ti/SiO2/Si substrate by the sol-gel method.The effect of annealing on their structures and ferroelectric properties was investigated.The XRD patterns indicate that the BLT films annealed at different temperatures are randomly orientated and the single perovskite phase is obtained at 550℃.The remmant polarization increnses and the coercive field decreases with the annealing temperature increasing.The leakage current density of the BLT films annealed at 700℃ is about 5.8×10^-8A/cm^2 at the electrie field of 250kv/cm.
文摘Using metallo-organatic compound TPT as the source of Ti, H13 mould steels were coated with Ti(CN) films by plasma-assisted chemical vapor deposition (PCVD) and the properties of Ti(CN) films were studied. Under the appropriate temperature and pressure, Ti(CN) films on H13 mould steel surfaces had the highest micro-hardness of HV1760 at 500°C, and the films showed excellent anti-oxidation property below 500°C. The lifetime of Ti(CN)-coated augers and dies could be enhanced 7 and 4 times longer than those of untreated respectively.