硅掺杂CVD金刚石薄膜

研究硅掺杂对CVD金刚石薄膜形貌、结构特性和成分的影响。通过向丙酮中加入正硅酸乙酯作为反应气体,在硅基底上沉积硅掺杂CVD金刚石薄膜。金刚石薄膜的表面形貌和显微组织由场发射电镜表征。金刚石薄膜的成分通过拉曼光谱和X射线衍射（XRD）进行研究。薄膜的表面粗糙度由表面轮廓仪评估。结果表明,硅掺杂会降低晶粒尺寸,促进晶粒细化并抑制三角锥形形貌。XRD研究表明,（111）朝向的晶面显著减少。拉曼光谱研究表明,硅掺杂会促进薄膜中硅碳键的形成以及非金刚石相的增多。在硅碳浓度比为1％时,沉积得到光滑的细晶粒金刚石薄膜。     

Morphological evolution of CdS films prepared by chemical bath deposition

In this article, the growth process of chemical bath deposited CdS films was systematically investigated. The structural, optical, and morphological properties were investigated by X-ray diffraction （XRD）, transmission electron microscope （TEM）, UV-Vis spectrophotometer, scanning electron microscope （SEM）, respectively. CdS nanocubes with size of less than 500 nm and nanocrystal-lites with diameter of less than 5 nm forming in reaction solution are observed. According to the TEM results and the SEM morphological evolution of CdS films, a crystal-lite-by-crystallite growth mechanism is proposed to eluci-date the growth process of chemical bath deposited CdS films based on the present growth mechanism.     

Sm（CoFeCuZr）12快淬薄带的晶体织构与磁性能各向异性

在辊表面速度为15～35 m/s的条件下制备Sm(Co0.68Fe0.20Cu0.08Zr0.04)12合金快淬薄带,对薄带的微观组织、晶体织构和磁性能各向异进行研究.结果表明:薄带的微观组织由成束的Th2Ni17型结构的2:17相取向柱晶在薄带平面内交织排列而成,每一束柱晶内各个柱晶之间互相平行,而各束柱晶的取向随机分布;随着辊速从15 m/s增加到35 m/s,柱晶宽度显著细化,在35 m/s时达到285 nm;当辊表面速度分别为15、25和35 m/s时,薄带自由面的衍射谱中衍射峰强度比(I(200)/I(111))分别为3.0、3.6和4.5,表明快淬薄带自由面存在(200)晶体织构并且随着辊速的增大而增强,2:17相柱状晶的易磁化方向[001]晶向则处于薄带平面内:平行于薄带平面方向的饱和磁化强度和剩磁比垂直于薄带平面方向的分别高出0.21-0.37 T和0.04-0.10 T;随着辊速从15 m/s增大到35 m/s,薄带的饱和磁化强度、剩余磁化强度和矫顽力都相应提高.     

Mechanical properties of silicon-doped diamond-like carbon films prepared by pulse-plasma chemical vapor deposition

Silicon-doped diamond-like carbon (Si-DLC) films were prepared by dc pulse-plasma chemical vapor deposition (CVD), using a mixture of acetylene (C₂H₂) and tetramethylsilane (TMS) as the material gas. The pulse voltage was varied from − 2 to − 5 kV, and the TMS flow ratio (TMS/(C₂H₂ + TMS)) was varied from 0 to 40%. At a pulse voltage of − 2 kV, an increase in TMS flow ratio leads to a decrease in hardness. In contrast, at a pulse voltage of − 5 kV, an increase in TMS flow ratio leads to a slight increase in hardness. The high hydrogen concentration in the films due to an increase in TMS flow ratio promotes the formation of polymeric sp³ C―H bonds, resulting in the fabrication of soft films at a low pulse voltage of − 2 kV. However, an increase in the effect of ion peening on the growth face results in the formation of hard films at a high pulse voltage of − 5 kV. Then, at a pulse voltage of − 5 kV fabricating hard Si-DLC films, an increase in TMS flow ratio leads to an increase in the silicon content in the films, resulting in a decrease in the friction coefficient. Therefore, it is clarified that Si-DLC films fabricated by dc pulse-plasma CVD under a high pulse voltage and high TMS flow ratio exhibit high hardness and a low friction coefficient. Moreover, to investigate the friction coefficient of Si-DLC films fabricated by dc pulse-plasma CVD, films deposited by dc plasma CVD were also evaluated. To obtain the same low friction coefficient, dc pulse-plasma CVD requires less TMS than dc plasma CVD. Hence, it is also clarified that Si-DLC films can be fabricated at a low cost by dc pulse-plasma CVD.     

Structure and magnetic properties of Co-P films of nanometer thickness

The main features of the formation of chemically deposited thin polycrystalline Co-P films of nanometer thickness have been determined experimentally. Changes in the surface structure of films with different thicknesses have been determined using an atomic force microscope. It has been established that at thicknesses smaller than 10 nm the films represent a set of weakly connected nuclei of crystallites with random orientations of easy axes. The subsequent increase in the thickness of films leads to the formation of a uniform polycrystalline layer. Estimates are given, which make it possible to determine the magnetic state of crystallites for the case of their weak magnetic interaction.     

Structural and mechanical properties of amorphous silicon carbonitride films prepared by vapor-transport chemical vapor deposition

The deposition of amorphous silicon carbonitride (a-SiCN:H) films has been successfully achieved through an in-house developed vapor-transport chemical vapor deposition (VT-CVD) technique in a nitrogenated atmosphere. Polydimethylsilane (PDMS) was used as a single-source precursor for both silicon and carbon, while NH₃ was mixed with argon to ensure the in-situ nitrogenation of the films. The chemical bonding and the atomic composition of the a-SiCN:H films were systematically investigated, as a function of their N content, by means of Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). AFM was used to obtain 2-D and 3-D views of the films. The mechanical properties [(hardness (H) and Young's modulus (E)] of the freshly prepared films were investigated by the nanoindentation technique. It is shown that by controlling the NH₃/Ar gas flow ratio in the reactor, a-SiCN:H films with various N contents [(0-27) at.% range] are achieved. On the microstructural level, the increase incorporation of N in the a-SiCN:H films is found not only to lead to C atom substitution by N atoms in the local Si-C-N environment but also to an enhanced incorporation of hydrogen bonded to both Si and N. Furthermore, the increase incorporation of N in the a-SiCN:H films resulted in an increase of the average R_rms surface roughness from 4 to 12 nm. Moreover, the films became porous with pore size and density increase as a result of increasing N at.%. Ultimately, both H and E of the a-SiCN:H films were found to be sensitive to their N content, as they decrease (from ~ 17 GPa and 160 GPa to ~ 13 GPa and 136 GPa, respectively) when the N content is increased from 0 to 27 at.%. The formation of Si-N, Si-H, and N-H bonds at the detriment of the more stiff Si-C bonds is thought to account for the observed lowering of the mechanical properties of the a-SiCN:H films as their N content increased.     

Crystalline anisotropy effect on magnetic properties and its competition with shape anisotropy

Shape and crystalline anisotropies compete when their easy axes are perpendicular. The critical aspect ratio, which is the aspect ratio required to offset the crystalline anisotropy, was observed in an effort to investigate the quantitative contribution of crystalline anisotropy using micromagnetic simulation. For a 0.25 μm width hcp-Co pattern, an aspect ratio of 2.7 is required in order to cancel out a crystalline anisotropy constant of 26 kJ/m³. The magnetic switching properties are also affected by crystalline anisotropy, which causes the magnetic domain to be narrowed during the reversal process.     

Nanocrystalline titanium nitride films prepared by electrophoretic deposition

Homogeneous and adhesive nanocrystalline TiN thin films are fabricated on Ti substrates by electrophoretic deposition in an aqueous suspension containing TiN powders at room temperature. X-ray diffraction confirms the formation of TiN films and the film color varies with deposition time. The current-time curves are recorded during deposition and the surface morphology and cross-sectional images are investigated by scanning electron microscopy (SEM). The film thickness is around 6.1 μm after 10 min deposition and increases with deposition time. The adhesion strength is characterized by the ultrasonic vibration method and peel-off test. Our results suggest that electrophoretic deposition is a practical and facile technique to prepare nanocrystalline TiN films that are particularly suitable for the decorative coating industry.     

化学气相沉积法制备铼材料的研究进展

铼具有优异的物理力学性能,作为功能材料及超高温结构材料获得广泛应用。铼材料的制备方法有多种,化学气相沉积（CVD）是其主要的制备方法之一。本文简要介绍了化学气相沉积制备铼材料的反应类型、沉积条件及沉积效果,综述了CVDRe材料的沉积动力学、组织结构特征、力学性能的研究现状和典型应用,并与粉末冶金铼进行了对比分析。最后指出了目前CVDRe材料研究亟待解决的关键问题,并对进一步研究的方向和推广应用前景进行了展望。     

ZnO薄膜的脉冲激光沉积及性能研究

利用脉冲激光沉积技术在氧的活性气氛下烧蚀锌靶,在石英玻璃衬底上沉积获得ZnO薄膜,分析并研究了薄膜的微观组织及表面形态及激光能量密度、基体温度、氧压等工艺参数对沉积ZnO膜的影响.结果表明,在基体温度为450～550 ℃、氧压为31 Pa、激光能量密度为31 J/cm2条件下,膜表面完全氧化,ZnO沿(002)晶面生长;当基体温度为500 ℃时,ZnO薄膜光学性能优异.     

Properties of chemically vapor deposited blanket tungsten films on tin glue layers prepared by chemical vapor deposition

The dependence of CVD W growth on various types of TiN layers was investigated with blanket and patterned wafers. There were no appreciable effects of the properties of TiN on the resistivity, structure, growth rate or reflectivity of CVD W in the case of blanket wafers; however, the stress of the W layer was found to be dependent upon the type of TiN glue layer adopted. W deposited on the TDMAT-TiN glue layer exhibits the lowest stress levels among the tested TiN films. TiCl₄-TiN proved to be superior to TDMAT-TiN from the viewpoint of W conformality. Although there was no appreciable effect of deposition temperature silane reduction time, contact size or shape of contact upon the W conformality on a TiCl₄-TiN layer, the W conformality on TDMAT-TiN was highly dependent on the above parameters, apparently caused by insufficiently plasma treated TiN on the side walls of contacts.     

Non-stoichiometry of titanium nitride plates prepared by chemical vapour deposition

Wide-ranging non-stoichiometric titanium nitride (TiN_x) plates (x = 0.74−1.0) were prepared by chemical vapour deposition from a TiCl₄-NH₃-H₂ system. The lattice parameter increased from 0.4228 to 0.4240 nm with increasing x. The density changed in the range between 5.1 and 5.4 × 10³ kg m⁻³, which is in agreement with theoretical values calculated from the lattice parameters and the compositions. The deposition domains of non-stoichiometric TiN_x were calculated thermodynamically as a function of input composition. The deposition mechanism of the non-stoichiometric TiN_x plates was discussed by comparing the calculations with experimental results.     

Growth mechanism of CdS film prepared by chemical bath deposition

In this paper, sodium citrate was adopted as a complexing agent and ammonia merely served as pH adjustor to investigate the growth mechanism of CdS film The growth rate, structural properties, surface morphology microstructure, and optical properties of CdS films were studied by profilometer, X-ray diffractometer（XRD）scanning electron microscopy（SEM）, transmission elec tron microscopy（TEM）, and spectrophotometer, respec tively. The SEM images show that CdS films prepared with higher ammonia concentration have lower nucleation density on substrate. SEM and EDS results show that the formation of Cd（OH）2is not required in the growth of CdS film. As the ammonia concentration increases, the sites tha previously adsorbed S2-are taken by OH-which leads to lower S2-density on substrate. CdS film forms through direct reaction of Cd2？with the S2-which are adsorbed on the substrate. Lower S2-density on the substrate results in the decrease of particle density on the substrate. The as deposited CdS films have relatively high-average trans mittance（＊80 %） in the wavelength range from 500 to1,000 nm which makes them suitable to be used in sola cell.     

Surface characterization and properties of silicon nitride films prepared by ion-assisted deposition

Silicon nitride (SiN) films had been prepared at low substrate temperature (100 °C) using the ion-assisted deposition (IAD) process. The films had been analyzed by the measurement of X-ray diffraction, atomic force microscopy, Fourier transform infrared spectrometry, nano indenter, and ellipsometry. The effects of N-ion current density on the surface morphology, compositional, mechanical, and infrared optical properties of SiN thin films were investigated. The results showed that the stoichiometric Si₃N₄ thin film with desirable properties, such as continuous and smooth surface morphology, extremely low hydrogen content, mechanical strong, and low extinction coefficient, could be obtained by using the IAD technique.     

Relationship between mechanical properties and chemical groups in a-C:F films prepared by RF unbalanced magnetron sputter deposition

a-C:F films were prepared by RF unbalanced magnetron sputter deposition on Si substrates. The modulus and hardness of the films and their relationship with chemical groups in the films were investigated. The results show that the modulus and hardness of the deposited films are not only determined by the nature of cross-link C-C network, but also affected by the fluorocarbon groups. The C-C network of the films is composed of sp² cluster, thus the modulus and hardness of films are close to those of polycrystalline graphite. Compared with other fluorocarbon groups existing in the films, the effect of -(CF-CF)_n- group on the modulus and hardness of the films is much higher. With increasing of -(CF-CF)_n- group proportion, modulus and hardness of the films linearly decrease.     

氮气对DC-PCVD法制备金刚石薄膜影响的研究

采用直流热阴极等离子体化学气相沉积方法,用甲烷、氢气、氮气的混合气体在Mo基底上成功制备了金刚石薄膜.分别采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、拉曼光谱仪(Raman)对不同流量氮气氛下生长金刚石薄膜的形貌、取向、质量进行了表征.结果表明:适量氮气的加入,不仅可以促进金刚石薄膜的生长速率,还可以促进金刚...     

Induced magnetic anisotropy in permalloy films annealed with magnetic field

The effect of magnetic annealing on Fe₂₁Ni₇₉ films was investigated through the characterization of crystal structure and magnetic properties. Fe₂₁Ni₇₉ films were deposited on thermally oxidized Si substrates using a DC magnetron sputter. A highly a-axis oriented Fe₂₁Ni₇₉ film was grown on Si substrate by magnetic annealing. Columnar grain growth was dominant in the films annealed with magnetic field. Both the area surrounded by hysteresis curve, and coercivity, were increased by magnetic annealing, indicating that the magnetic annealing induced the anisotropy energy. Through EXAFS analysis, 1.19×10^?3 was obtained as the strain of a specimen annealed with magnetic field. This value confirmed that induced magnetic anisotropy was formed by atomic pair ordering.     

钛合金表面离子束增强沉积MoS2基膜层及其性能

将离子束增强沉积（IBED）技术与离子束溅射的沉积技术相结合,在钛合金表面制备了MoS2,MoS2-Ti复合膜。研究了膜层的形态、结构、膜基结合强度、硬度、摩擦学性能及抗微动（fretting）损伤性能。结果表明;所获膜层较纯溅射膜结合强度高、致密性好,复合膜中允许的金属元素含量大。通过恰当地控制复合膜中Ti的含量,可获得以（002）基面择优取向的MoS2-Ti复合膜,该膜层有较好的减摩和抗磨综合性能,能够显著地改善钛合金的常规磨损、微动摩员（FW)和微动疲劳（FF）性能,特别是在磨损严重的大位移整体滑条件下,MoS2-Ti复合膜对钛合金FF抗力的提高作用可大于喷丸形变强化处理。     

Time-modulated chemical vapor deposition of diamond films

This article investigates the role of substrate temperature in the deposition of diamond films using a newly developed time-modulated chemical vapor deposition (TMCVD) process. TMCVD was used to deposit polycrystalline diamond coatings onto silicon substrates using hot-filament chemical vapor deposition system. In this investigation, the effect of (a) substrate temperature and (b) methane (CH₄) content in the reactor on diamond film deposition was studied. The distinctive feature of the TMCVD process is that it time-modulates CH₄ flow into the reactor during the complete growth process. It was noted that the substrate temperature fluctuated during the CH₄ modulations, and this significantly affected some key properties of the deposited films. Two sets of samples have been prepared, in each of which there was one sample that was prepared while the substrate temperature fluctuated and the other sample, which was deposited while maintaining the substrate temperature, was fixed. To keep the substrate temperature constant, the filament power was varied accordingly. In this article, the findings are discussed in terms of the CH₄ content in the reactor and the substrate temperature. It was found that secondary nucleation occurred during the high timed CH₄ modulations. The as-deposited films were characterized for morphology, diamond-C phase purity, hardness, and surface roughness using scanning electron microscopy, Raman spectroscopy, Vickers hardness testing, and surface profilometry, respectively.     

Direct deposition of CeO2 films on Ni metal substrate by chemical vapor deposition

Cerium dioxide thin films have been grown in-situ directly on cube textured Ni substrate by metal-organic chemical vapor deposition (MOCVD). At a lower deposition temperature of 400°C, an amorphous film was formed. The texture of crystalline CeO₂ film was changed from (200) orientation to (111) orientation when the deposition temperature was increased from 450°C to 550°C. The growth rate was ~40 nm/min and the rms surface roughness was 50 nm for the CeO₂ film deposited at 450°C for 10 min. Surface roughness of the film was increased with the development of (111) orientation. Deposited CeO₂ film showed a mixed texture of (100)<001> and (100)<011> orientation. Depending on the deposition condition, the transition from (100)<001> texture to (100)<011> orientation was observed.