三柱靶磁控溅射镀膜机在工艺品装饰镀中的应用

将三柱靶磁控溅射镀膜机应用于工艺品装饰镀生产中,开发多种镀膜工艺并进行了批量生产,实践证明:三柱靶磁控溅射镀膜技术结合特制的衬底漆和保护面漆涂装工艺,能够在工艺品上获得合格的装饰层.拓展该技术在工艺品行业的应用,可有效减轻传统电镀对环境的污染.     

Fully strained low-temperature epitaxy of TiN/MgO(001) layers using high-flux, low-energy ion irradiation during reactive magnetron sputter deposition

Epitaxial TiN layers, 0.3 μm thick, are grown on MgO(001) in the absence of applied substrate heating using very high flux, low-energy (below the lattice atom displacement threshold), ion irradiation during reactive magnetron sputter deposition in pure N₂ discharges. High-resolution x-ray diffraction, reciprocal lattice maps, and transmission electron microscopy analyses reveal that the TiN(001) films grow with an (001)_TiN||(001)_MgO and [100]_TiN||[100]_MgO orientation relationship to the substrate. The layers are fully coherent with no detectable misfit dislocations. For comparison, TiN/MgO(001) films grown at temperatures of 700-850 °C under similar conditions, but with no intentional ion irradiation, are fully relaxed with a high misfit dislocation density. Thus, the present results reveal that intense low-energy ion irradiation during film growth facilitates high adatom mobilities giving rise to low-temperature epitaxy, while the low growth temperature quenches strain-induced relaxation and suppresses misfit dislocation formation.     

磁控溅射镀膜中工作气压对沉积速率的影响

沉积速率是磁控溅射镀膜技术中的一项重要指标,它由许多因素决定.为了定性地了解沉积速率与工作气压之间的关系,通过实验测定了不同工作气压下的沉积速率,发现存在一个最大值,并对应有一个最佳工作气压.运用气体放电理论对这一现象进行了分析.这个结论为提高薄膜制备效率指明了方向,并为进一步建立沉积速率与工作气压之间的数学模型打下了基础.     

A combined sensor for the diagnostics of plasma and film properties in magnetron sputtering processes

A combined sensor for the simultaneous measurement of plasma and deposition parameters has been designed and built. It comprises (i) a quartz crystal microbalance, (ii) a planar Langmuir probe and (iii) a calorimetric (Gardon) probe, which allows to measure the deposition rate, typical plasma parameters (plasma density and electron temperature) and the total energy input into a growing film. The combined sensor is electrically insulated against ground, allowing these measurements also for floating or substrate-bias conditions. These parameters are measured (nearly) simultaneously, controlled by a specific measurement and analysis program. The operation of this combined sensor is demonstrated for the deposition of copper and tungsten films with a 2 inch planar magnetron.     

O density measurements in the pulsed-DC reactive magnetron sputtering of titanium

Using eclipse laser photo-detachment in conjunction with Langmuir probing, the density of O⁻ ions in a reactive pulsed magnetron (100 kHz, 55% duty) plasma has been determined at different times during the pulse period at a set of positions along the centre line axis of the discharge. The magnetron was operated at a fixed average power of 400 W with an oxygen partial pressure of 10% of the total pressure 1.33 Pa. The results show the plasma is weakly electro-negative, with a negative ion-to-electron density ratio α up to a maximum of 0.63.During the plasma on-phase (at all chosen measurement positions) the O⁻ density was found to reach a maximum directly after initiation of the voltage pulse decreasing weakly during the rest of the on-phase. On the transition from on-to-off phases of the pulse the negative ion density was found to fall (by 60% both close and far from the target but only 10% near the discharge centre), with the O⁻ density remaining almost constant during the rest of the afterglow.The spatial structure of the O⁻ density reveals a distinct peak 75 mm from the target close to but not at the position of the null in the magnetic field, falling by a factor of eight for increasing distances up to 30 mm both towards and away from the target. The highest O⁻ density recorded at this position was 1 × 10¹⁶ m⁻³, at a time of 2.12 μs into the pulse. From a comparison between on- and off-phase densities and using an intuitive model of the plasma, the results indicate that most negative ions are created in the bulk plasma. The density of target-borne O⁻ ions is estimated to be about 1 × 10¹⁵ m⁻³ varying little with position, possibly forming a beam-like structure.     

A novel Ti cored wire developed for wire-feed arc deposition of TiB/Ti composite coating

A novel Ti cored wire containing TiB2,Al60V40 and Ti6Al4V mixed powders was developed for wire-feed arc deposition of TiB/Ti composite coating,to enhance the hardness and wear resistance of Ti alloy.Results showed that after experiencing several chemical reactions,the wire was melted in the arc zone and turned into nonuniform droplets composed of Ti-Al-V-B melt and undecomposed TiB2 particles.With the increase of welding current,the detachment time of droplet shortened while the transfer frequency accelerated,accompanied by the improvement in coating surface quality.The spatial distribution of TiB whiskers in coating was governed by welding current.A uniform distribution could be achieved as welding current was sufficient at the expense of elevated dilution ratio,while increasing wire feeding speed could compensate the dilution loss of TiB whisker to some extent.The decomposition process of TiB2 particles and the microstructure evolution mechanism of coating was discussed in detail.The optimum coating possessed uniform microstructure,relatively low dilution ratio,and high hardness(639.1 HV0.5)as compared with Ti6Al4V substrate(326 HV0.5).Indentation morphology analysis verified the excellent performance was ascribed to the load-sharing strengthening of TiB whiskers.This study provides a high-efficiency fabrication method for the ever-developing titanium matrix composites(TMCs)coating.     

Structural changes in tungsten wire and their effect on the properties of hydrogenated nanocrystalline cubic silicon carbide thin films

We investigated the structural changes in tungsten wire heated to 1800 °C in SiH₄/CH₄/H₂/N₂ atmosphere and the effect of the aging tungsten wire on the properties of N-doped hydrogenated nanocrystalline cubic silicon carbide (nc-3C-SiC:H) thin films. The aged tungsten wire had two parts: hot parts of the middle of the wire and relatively cold parts connected to clamps. Tungsten carbide (W₂C) layer formed in the wire of the hot parts, while crystalline silicon and cubic silicon carbide (c-Si/3C-SiC) layer deposited on the wire of the cold parts. N-doped nc-3C-SiC:H thin films were deposited for 5 min (thickness: ~ 30 nm) after the tungsten wire was heated under the same condition as during the film deposition for given times (exposure time). No changes in the structural, electrical and optical properties of the nc-3C-SiC:H thin films were observed for the exposure time up to 450 min.     

Initiated chemical vapor deposition of a siloxane coating for insulation of neural probes

Recent advances in the field of neuroprosthetics have brought the possibility of human utilization into the near term. However, current implant coating chemistries require thicknesses of ~ 25 μm in order to provide the required electrical insulation, significantly increasing the diameter of the neural probe shanks and resulting surgical damage upon implantation. In this work, a novel biopassivation coating is created through initiated chemical vapor deposition (iCVD) of trivinyl-trimethyl-cyclotrisiloxane. The resulting material is a highly crosslinked organosilicon polymer matrix which is synthesized directly on the surface of the substrate. This material possesses an electrical resistivity which allows for a coating thickness on the order of only 5 μm. The material has also been demonstrated to retain its electrical properties in a simulated biological environment for over 3 years.     

On the bending of a stretched wire - case study of a tension measuring device

The case of a stretched wire bent successively over a system of three pulleys has been analysed with specific reference to a commonly used wire tension measuring device. With the help of the simple theory of elastic bending, expressions for the tension variation, angles of wrap, deflections etc., at the pulley have been obtained. A brief parametric study leads to some useful design guidelines. The analysis can be usefully applied to other systems also where wirelwire rope is bent over multiple pulleys.     

Plasma parameters in the vicinity of the quartz window of a low pressure surface wave discharge produced in O2

Plasma parameters in the vicinity of the dielectric window of a low density, microwave discharge produced in O₂ at 915 MHz are investigated by a spherical probe and optical emission spectroscopy while the microwave field distribution is measured by a spectrum analyzer. The electron energy distribution function is found to be strongly dependent on the position with respect to the slot antenna, exhibiting a group of energetic electrons at locations where the electric field and the optical intensity exhibit maximum values. The density of energetic electrons decreases sharply just a few cm away from the dielectric.     

Measurement of the input resistance of a rf biased SQUID

Measurements of the real part of the input impedance of a RF biased SQUID are described. The experimental data are in good agreement with the predictions of the recently published theory. In particular the dependence of the input resistance on the detuning of the rf bias frequency from tank circuit resonance frequency is confirmed.     

Spectral and angular characteristics of the radiation from a cylindrical radionuclide source

Translated from Izmeritel'naya Tekhnika, No. 2, pp. 13–16, February, 1993.     

IAD技术在钼酸铅晶体表面镀膜中的应用

讨论了离子束辅助沉积技术在真空沉积过程中的应用原理。通过与常规的热蒸发工艺镀制的膜层相比较，证实了离子束辅助沉积技术有助于提高钼酸铅晶体表面红外增透膜的膜层品质及中心波长位置的精确度。     

Effects of the centrifugal coating and centrifugal fluidized bed coating methods on the physicochemical properties of sustained-release microparticles using a multi-functional rotor processor

The purpose of the present study was to examine the effect of coating processes on the physicochemical properties of sustained-release microparticles prepared by centrifugal coating (CC) and centrifugal fluidized bed coating (CFC) using a multi-functional rotor processor. Acetaminophen (APAP)-loaded microparticles (DP) were coated with 30% w/w aqueous polymer dispersion of Eudragit® RS (RS) by CC or CFC methods with the apparatus until a dry polymer weight gain of 30%, 60%, 150% and 200% w/w was achieved, and these coated microparticles were abbreviated as CC-DP-RS and CFC-DP-RS, respectively. Both coated microparticles had similar physicochemical properties, but some differences in the drug dissolution behaviors of CC-DP-RS and CFC-DP-RS at lower coating levels were observed. That is, the coated microparticles prepared by CC showed faster release than that by CFC. As a result of dissolution study using Talc seal-coated microparticles and thermal study using differential scanning calorimeter, the rapid dissolution behaviors from CC-DP-RS at the lower coating levels of RS might be due to APAP migration to the coating film during coating due to the weak drying efficacy of the CC method. These findings suggest for the first time that CFC is a suitable method for the coating of functional polymers at lower polymer coating levels, whereas, for the CC method, adjustment of operational conditions (e.g., product temperature, inlet air volume and liquid flow rate) would be required.     

本底真空度对非平衡磁控溅射C/Cr复合镀层性能的影响

采用非平衡磁控溅射在GW93镁合金表面制备了镀C/Cr复合镀层,分析了不同本底真空度下在GW93镁合金表面进行非平衡磁控溅射镀C/Cr复合镀层的硬度、耐蚀性、膜基结合力,摩擦系数等.结果表明,非平衡磁控溅射镀C/Cr复合膜层,本底真空度在8.8×10-3～1.0×10-1Pa范围内,镀层硬度与本底真空度成反比,当其为8.8×10-3Pa时,镀层硬度最低为1397Hv0.05,镀层使基体自腐蚀电位提高到-0.940V,显著改善镁合金的耐蚀性,结合力最高可达8.11N,镀层的摩擦系数最低达到0.05.本底真空度对C/Cr复合镀层相组成没有显著影响,不同真空度下的C/Cr复合镀层均以非晶为主.     

Characterization of the degraded microstructures of a platinum aluminide coating

The degradation of a platinum modified aluminide (PtAl) coating and a CMSX-4 superalloy substrate were investigated for cyclic and quasi-isothermal heating to 1200 °C. To accelerate the oxidation of the specimens, the thermally grown oxide (TGO) was removed at 10 h intervals. For up to 80 h of exposure, comparisons of specimens with periodic oxide removal and those without oxide removal were made. Qualitatively, the major changes to the bond coat were associated with phase changes from β-(Ni,Pt)Al to γ′-(Ni₃Al) and precipitate coarsening. This evolution was quantified through backscatter scanning electron microcopy and image analysis. With instrumented indentation, the room temperature coating modulus was also measured at 10 h intervals. Additional results include observations of differences in waviness of the bond coat surface for cyclic, quasi-isothermal, and true-isothermal heating, and observations of rafting near the substrate/coating interface. The differences between cyclic and quasi-isothermal heating indicate that stresses associated with cooling and heating significantly alter microstructural evolution.     

Effect of the substrate temperature on the properties of Ga-doped ZnO films for photovoltaic cell applications deposited by a pulsed DC magnetron sputtering with a rotating cylindrical target

Effect of substrate temperature on the properties of Ga-doped ZnO (GZO) films was investigated by pulsed DC magnetron sputtering with a rotating cylindrical target with an aim to establish suitable process conditions for their photovoltaic (PV) cell applications. Without formation of undesirable secondary oxide phases such as Ga₂O₃ and ZnGa₂O₄, the GZO film having mixed orientation at lower deposition temperature evolved into the c-axis oriented one with increasing deposition temperature to 230 °C, which accompanied morphological evolution to vertically oriented dense columnar structure and improved doping efficiency. Correlated with this, crater-like surface texturing was possible only on the sample deposited at 230 °C. Electrical resistivity and diffuse surface reflectance over the spectral range of 200-1200 nm of this GZO film after surface texturing were 8.73 × 10⁻⁴ Ω cm and 3.32%, respectively, indicating that the film has application potential as anti-reflection coating and front electrode of PV cells. Morphological features, surface texturing behavior, electrical and optical properties of the GZO films in this study suggest that this novel technique would be applicable to the fabrication of anti-reflection coating and front electrode of PV cells only when substrate temperature is sufficiently high.     

Hot wire chemical vapor deposition: limits and opportunities of protecting the tungsten catalyzer from silicide with a cavity

Hot Wire Chemical Vapor Deposition (HW-CVD) is one of the most promising techniques for depositing the intrinsic microcrystalline silicon layer for the production of micro-morph solar cells. However, the silicide formation at the colder ends of the tungsten wire drastically reduces the lifetime of the catalyzer, thus limiting its industrial exploitation. A simple but interesting strategy to decrease the silicide formation is to hide the electrical contacts of the catalyzer in a long narrow cavity which reduces the probability of the silane molecules to reach the colder ends of the wire. In this paper, the working mechanism of the cavity is elucidated. Measurements of the thickness profile of the silicon deposited in the internal walls of the cavity have been compared with those predicted using a simple diffusion model based on the assumption of Knudsen flow. A lifetime study of the protected and unprotected wires has been carried out. The different mechanisms which determine the deterioration of the catalyzer have been identified and discussed.     

Construction and characterization of a sputter deposition system for coating granular materials

In many modern ceramic or metal matrix composites the interface between the matrix and the reinforcements (particles or fibres) plays an important role. Either no or only weak mechanical bonding is observed or severe reactions between the matrix and the filler during the manufacturing process take place. A method to promote adhesion or to avoid severe reactions is to use coated reinforcements. A uniform film can act as an adhesion promoter, a compliant layer, a reaction inhibitor or a promoter of thermal transport across the interface.The aim of this work was to construct a particle coating system based on magnetron sputter deposition which allows to keep the particles or the granular material in motion during the deposition process to guarantee a homogenous coating on every single particle. As particles to be coated diamond granulates and carbon fibres were investigated. For transparent diamond particles the uniformity of a metallic coating could be evaluated by transmission optical methods and was found to be quite high. Carbon fibres, on the other hand, could only partially be coated due to agglomeration and shadowing effects. The system presented here can be considered as suitable for coating spherical or close to spherical granular matter.     

四硼酸钠对化学镀镍磷非晶镀层镀速及耐蚀性能的影响

采用化学镀的方法在45#碳钢试样表面制备了四硼酸钠(硼砂)促进Ni-P沉积的非晶镀层。利用扫描电子显微镜和X射线观察及分析了镀层的表面形貌与表面结构,研究了四硼酸钠的浓度对非晶镀层的表面形貌、沉积速率、P含量、孔隙率以及耐蚀性能的影响。结果表明,添加一定量的四硼酸钠能使镀层晶粒更加细化,分布更为均匀,镀层的沉积速率有很大的提高。随着四硼酸钠含量的增加,沉积速率逐渐升高,而镀层中的磷含量逐渐降低。当四硼酸钠的含量超过2.5g/L时,镀液的稳定性会大大的降低;镀速达到最大值21.35μm/h;磷含量最低为14.3%。四硼酸钠的加入对镀层的耐蚀性影响不大,但可以提高沉积速率从而提高镀层的使用周期,具有很好的经济效益和使用价值。