类金刚石薄膜的离子注氮研究

以25～35kV的高能离子束将离子化的双原子分子N+2注入非晶态碳膜,硬度可提高10GPa量级.分析研究表明:离子注氮并没有改变碳膜的非晶态结构,但所有拉曼结构参数发生变化,且碳、氮结合能峰位发生化学位移;显然注入的氮和碳形成化学键,并可能形成新相. 结论:类金刚石薄膜离子注氮可合成氮化的类金刚石,改变化学结构,提高机械性能.     

Adhesion of NiCu Films DC Biased Plasma-Sputter-Deposited on MgO (001)

NiCu films about 60nm thick were deposited on MgO (001) substrates at 230℃ by DC plasma-sputtering at 2.7kV and 8mA in pure Ar gas using a Ni90Cu10 target. A DC bias voltage of 0, 60, 110 or 140V was applied to the substrate during deposition. The adhesion of the film to the substrate was studied using a scratch test as a function of . The application of is very effective in increasing the adhesion of the film to the substrate. In conclusion, the adhesion increases with cleaning the substrate surface by sputtering off impurity admolecules during the film initial formation due to the energetic Ar ion particle bombardment.     

采用石墨碳源沉积金刚石薄膜

采用固相石墨为碳源，使用微波等离子体化学气相沉积（MPCVD）法，在Si(111)上沉积高质量的金刚石薄膜。研究了在气相碳源浓度处于不饱和状态时，沉积气压和石墨温度对生长速率的影响。利用SEM，XRD，红外光谱分析薄膜表面形貌和质量。结果表明高质量的金刚石薄膜可在H2激发而生的封闭的等离子体气氛下合成，高的有沉积气压和石墨温度会导致高的气相碳源浓度，从而有利于提高薄膜的生长速率，而低的气相碳源浓度有利于沉积薄膜的质量的提高。     

PAHFCVD金刚石膜表面形貌的研究

采用等离子辅助热丝化学气相沉积(PAHFCVD)装置进行了金刚石薄膜、碳化钛/金刚石复合膜、掺硼金刚石薄膜的制备。制备条件分别为:V(CH)4∶V(H2)=3∶100,载气流量5~50 cm3.s─1,钛源钛酸异丙酯(Ti[OC3H7]4),硼源硼酸三甲酯(BC3O4H9),基体温度820~860℃,基体偏压300 V,沉积气压4 kPa。运用扫描电子显微镜(SEM)、X射线衍射(XRD)和能量扩散电子谱(EDX)等分析手段对PAHFCVD金刚石膜、金刚石复合膜和掺硼金刚石膜进行了表征。结果发现,金刚石/碳化钛膜和掺硼金刚石膜主要晶面为(111)面。     

中频非平衡磁控溅射TiAlN薄膜的结构与性能

采用中频非平衡磁控溅射离子镀设备在YG10硬质合金表面制备(Ti_1-xAl_x)N薄膜,运用X线衍射仪、扫描电子显微镜、显微硬度计和材料表面性能测试仪等对薄膜进行表征,分析氮气分压、直流偏压和Al含量对薄膜的力学性能、薄膜成分和组织结构的影响。结果表明:薄膜呈柱状多晶组织,主要组成相为(Ti, Al)N相;随着氮气分压增大,膜层中氮原子增多,而铝、钛原子含量减少,膜层中r_Al/(Al+Ti)与r_(Al+Ti)/N均下降,薄膜(111)晶面取向减弱,(220)和(200)晶面取向增强。力学性能测试表明,随着膜层中的Al含量和直流偏压升高,薄膜硬度、膜厚和膜-基结合力均呈现先升高后降低的趋势,薄膜显微硬度最高2 915 HV,膜-基结合力最高达73 N。     

Structure and Composition of Crystalline Carbon Nitride Films Synthesized by Microwave Plasma Chemical Vapor Deposition

Crystalline carbon nitride thin films were prepared on Si (100) substrates by a microwave plasma chemical vapor deposition method, using CH4/N2 as precursor gases. The surface morphologies of the carbon nitride films deposited on Si substrate at 830℃ are consisted of hexagonal crystalline rods. The effect of substrate temperature on the formation of carbon nitrides was investigated. X-ray photoelectron spectroscopy analysis indicated that the maximum value of N/C in atomic ratio in the films deposited at a substrate temperature of 830℃ is 1 .20, which is close to the stoichiometric value of C3N4. The X-ray diffraction pattern of the films deposited at 830℃ indicates no amorphous phase in the films, which are composed of β- and α-C3N4 phase containing an unidentified C-N phase. Fourier transform infrared spectroscopy supports the existence of C-N covalent bond.     

Surface characteristics and structure of oxide films containing Ca and P on Ti substrate

The oxide films were obtained in an electrolyte of calcium glyeerphosphate (Ca-GP) and calcium acetate (CA) by mieroare oxidation (MAO). The oxide films displayed a porous and rough structure on the film surface, and the roughness tended to increase with inereasing voltage of mieroare oxidation. The oxide film exhibited a uniform coating and tends to be well boned to the substrate. The thiekness of oxide films depended on the final voltage at a eonstant concentration of eleetrolyte solution. Ca and P were also incorporated into the oxide film during the mieroarc oxidation process, It was found that the electrolyte of ealeium glyeerphosphate ( Ca-GP) and ealeium acetate (CA) was suitable for microarc oxidation to form oxide film eontaining Ca and P on Ti substrate. The eoneentration of Ca and P were 11.6 at% and 6. 4 at% , respectively, when microare oxidation was performed in the electrolyte of 0. 06 M Ca-GP and 0. 25 M CA at current density 50 A/m^2 and final voltage 350 V. The composition of the Ca, P and Ti changed during depth profiling. The crystalline phases were only anatase when final voltage was below 300 V and rutile was presented when voltage was up to 350V. The microstructure, phase structure and phase composition were investigated by scanning electron microscopy (SEM) , atomic foree microscope (AFM) , energy dispersive X-ray mieroanalyser (EDX) , and X-ray diffraction (XRD),     

Structure and performance of TiC-containing diamond-like carbon nanocomposite coatings deposited by rectangular cathodic arc ion-plating

TiC-containing diamond-like carbon (TiC-DLC) nanocomposite coatings were deposited by a rectangular cathodic arc ion-plating system using C₂H₂ as reacting gas. Raman spectroscopy and transmission electron microscopy analysis show that with increasing flow rate of C₂H₂, the structure of nanocomposite coatings changes from TiC nanograin-containing to graphite nanograin-containing DLC. The hardness measurements show that the hardness decreases from 28 GPa to 18 GPa with increasing C₂H₂ flow rate. The scratch test show that a high critical load (>40 N) was obtained and exhibited a good adhesion between the coating and the substrate. Wear experiment shows that the friction coefficient of TiC-DLC nanocomposite coatings decreases with increasing C₂H₂. A low friction coefficient of 0.07 was obtained at 480 sccm C₂H₂.     

Extraordinary self-lubrication properties of non-hydrogenated diamond-like carbon films under humid atmosphere

Tribological properties of non-hydrogenated diamond-like carbon (DLC) films were investigated under humid (RH=80%) and dry (RH=5%) air. These films were deposited by pulsed laser deposition (PLD) at different substrate temperatures. Tribological properties of DLC fabricated by PLD is not sensitive to the relative humidity of testing environment. Because of the unique growth mechanism of DLC prepared by PLD, DLC is of “soft-hard” double layers, having a very low friction coefficient and wear rate under humid atmosphere. The minimum coefficient and wear rate of film under humid circumstance are 0.045 and 5.94×10⁻¹⁰ mm³N⁻¹m⁻¹, respectively, just a little bit more than those under dry condition. The root means square roughness of film is less than 1 nm. The sp³ content of film grown at room temperature (RT) is 72%, and the sp³ content decreases with temperature. Raman spectrum shows that the micro-structure is amorphous network. The largest hardness and elastic modulus of film are 51 GPa and 350 GPa, respectively and they reduce with increase of deposition temperature too. Water contact angles on surface are more than 90° which indicates that films fabricated by PLD are hydrophobic with low surface energy.     

Deposition of DLC Coating on Biomedical TiNi Alloys by Plasma Based Ion Implantation to Improve Surface Properties

1Introduction Diamond likecarbon(DLC)isbeingconsideredfor widespreadclinicaluseasasurfacecoatingforcoronary stents,heartvalvesandorthopaedicimplants.Sucha coatingofmedicalimplantshashighpotentialbenefits suchasreductionofmetalionreleasewhichleadstoare ductionofcoronarystent associatedthrombosis;lowfric tioncoefficientwhichensureslesswearparticlesreleaseof orthopaedicimplants;goodbiocompatibilitywhichlowers theriskofimplantfailure.Uptodate,DLChavebeen successfullycoatedon316Lstainlesssteel[1…     

纳米碳纤维薄膜的制备及其疏水性能

采用化学气相沉积(CVD)方法,以乙炔(C2H2)为碳源,直接于铜基板上生长碳纤维薄膜。铜基板只进行简单的打磨处理。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)对产物的形貌、结构进行了表征,并用接触角测量仪(CA)对制备的碳纤维薄膜进行疏水性测试。结果表明:在铜基板表面制备了一层直径为100～200nm,厚度为40～50μm的碳纤维薄膜。疏水测试结果显示,这种薄膜有较好的疏水性能,且随纳米碳纤维合成温度变化而变化。经多次试验表明,铜片具有良好的循环使用性能,可多次用于制备碳纤维薄膜。     

Effect of interface layers on electron field emission properties of amorphous diamond films

Hydrogen-free high sp~3 content amorphous diamond (AD) films are deposited on three different substrates——Au-coated Si (Au/Si), Ti-coated Si (Ti/Si) and Si wafers. Electron field emission properties and fluorescent displays of the above AD films are studied by using a sample diode structure. The compositional profile of the interfaces of AD/Ti/Si and AD/Si is examined by using secondary ions mass spectroscopy (SIMS). Because of the reaction and interdiffusion between Ti and C, the formation of a thin TiC intermediate layer is possible between AD film and Ti/Si substrate. The field emission properties of AD/Ti/Si are sufficiently improved, especially its uniformity. A field emission density of 0.352 mA/cm~2 is obtained under an electric field of 19.7 V/μm. The value is much more than that of AD/Au/Si and AD/Si under the same electric field.     

Influence of negative bias voltage on the mechanical and tribological properties of MoS<Subscript>2</Subscript>/Zr composite films

MoS2/Zr composite films were deposited on the cemented carbide YT14 (WC+14%TiC+6%Co) by medium-frequency magnetron sputtered and coupled with multi-arc ion plated techniques.The influence of negative bias voltage on the composite film properties,including adhesion strength,micro-hardness,thickness and tribological properties were investigated.The results showed that proper negative bias voltage could significantly improve the mechanical and tribological properties of composite films.The effects of negative ...     

The study of adsorption gas sensor based carbon nanotube film

The carbon nanotube is a hollow canaliculus like rolling up hexagon network graph- eme sheets, which is similar to the structure of the graphite. Its outer diameter is from a few nanometers to several decade nanometers. There are two kinds of them: single wall carbon nanotubes (SWNTs) and multi-wall nanotubes (MWNTs), all of which have the helix structure. People have paid great attention to them due to their interesting physical properties[1―3]. The elementary study results show that the…     

ZStructural and Electrical Properties of Cu Films by dc Biased Plasma-Sputter-Deposited on MgO(001)

Cu films of 30nm and 15nm thick were deposited on MgO(001) s ubstrates at 185℃ by dc plasma-sputtering at 1.9kV and 8mA in pure Ar gas. A dc bias voltage Vs of 0V or 80V was applied to the substrate d uring deposition. Structural and electrical properties have been inves tigated by cross-sectional transmission electron microscopy (XTEM), hi gh resolution XTEM (XHRTEM) and by measuring temperature coefficient o f electrical resistance (TCR; 　) in the temperature interval of 135℃ to 0℃. The Cu film is polycrystalline at Vs=0V while it epitaxially grows with Cu(001)‖MgO(001) and Cu[010]‖MgO[010] at Vs=80V. However, the latter has a very rough surface. The change of 　 with film thick ness and Vs is interpreted in terms of the structure change. Misfit di slocations and lattice expansion are induced along the MgO surface to relax the strain energy due to the lattice mismatch between Cu and MgO .     

Double Glow Plasma Hydrogen-free Carburizing on Commercial Purity Titanium

A carburized layer with special physical and chemical properties was formed on the surface of commercial purity titanium by a double glow plasma hydrogen-free carburizing technique,High-purity netlike solid graphite was used as a raw material and commercial purity titanium was used as the substrate material.Argon gas was used as the working gas.The carburized layer can be obviously observed under a microscope.X-ray diffraction indicates that TiC phase with higher hardness and dissociate state carbon phase was formed in the carburized layer.The glow discharge spectrum（GDS） analysis shows that the carbon concentration distributes grodiently along the depth of carburized layer.The surface hardness of the substrate increases obviously.The hardness distributes gradiently from the surface to inner of carburized layer.The friction coefficient reduces by more than 1/2,the ratio wear rate decreases by above three orders of magnitude.The wear resistance of the substrate material is improved-consumedly.     

Growth of graphite film over the tops of vertical carbon nanotubes using Ni/Ti/Si substrate

A substrate with Ni/Ti/Si structure was used to grow vertical carbon nanotubes (CNTs) with a graphite film over CNT tops by thermal chemical vapor deposition with CH4 gas as carbon source.The carbon nanotubes and the substrate were character-ized by a field emission scanning electron microscope for the morphologies,a transmission electron microscope for the microstruc-tures,a Raman spectrograph for the crystallinity,and an Auger electron spectrometer for the depth distribution of elements.The re-sult shows that when the thickness ratio of Ni layer to Ti layer in substrate is about i,a graphite film with relatively good quality canbe formed on the CNT tops.     

脉冲多弧离子镀沉积类金刚石薄膜的牢固度研究

利用脉冲多弧离子镀技术在硅基片上沉积类金刚石薄膜．分析了类金刚石薄膜的牢固度与各种工艺条件的关系．实验结果表明：基片的清洗、基片温度、主回路电压、脉冲频率、烘烤处理都强烈影响类金刚石薄膜的牢固度．同时从理论上分析了利用离子束辅助蒸发工艺可以进一步提高类金刚石薄膜的牢固度     

ZrO2 与TiO2 介孔薄膜对碳基介孔型钙钛矿太阳能电池的 性能影响

通过旋涂ZrO_2与TiO_2混合浆料,制备钙钛矿太阳能电池介孔层。以孔径较大的ZrO_2/TiO_2混合介孔薄膜(MIX)为基底制备了晶粒较大的甲胺铅碘(MAPbI3)钙钛矿光吸收层。以致密TiO_2薄膜为电子传输层,石墨/碳黑为对电极,制备了钙钛矿太阳能电池。比较了ZrO_2单层介孔、Ti O2单层薄膜、TiO_2+ZrO_2双层介孔与ZrO_2/TiO_2单层混合介孔的钙钛矿太阳能电池的性能。结果表明,用MIX制备的钙钛矿太阳能电池表现出最高的光电转换效率(PCE)和良好的长期稳定性。     

基板法催化生长纳米碳纤维薄膜

以乙炔(C2H2)为碳源,铜溶胶和硫化铜为催化剂前躯体,采用化学气相沉积法(CVD)在玻璃基板上生长纳米碳纤维薄膜。通过扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线衍射仪(XRD)对产物的形貌与结构进行了表征。结果表明:在反应温度为350℃时,制备出了纤维直径为100～200nm,厚度为3～20μm的均匀的纳米碳纤维薄膜;随着反应温度升高或者反应时间的延长,纳米碳纤维薄膜的膜厚增厚。