HgCdTe晶体上Cd和Te的阴极共沉积

在ＨｇＣｄＴｅ晶体表面上用电化学方法得到了Ｃｄ和Ｔｅ的共沉积．所用的电解质由Ｈ２ＳＯ４；ＣｄＳＯ４和ＴｅＯ２的水溶液所组成．稳态沉积电流密度随着沉积电位更负，电解质温度升高和ＴｅＯ２浓度的增加而增大．Ｘ光衍射分析证实，当沉积电位比－０．７０Ｖ（ｖｓＳＣＥ）更负时，沉积膜由ＣｄＴｅ和Ｃｄ所组成．当沉积电位比－０．６７５Ｖ更正时，沉积膜为化学计量的多晶ＣｄＴｅ，其（１１１）面为优先生长的晶面族．沉积膜的显微照相可能表明多层ＣｄＴｅ的扁平晶粒逐步长大连成一体后而完全复盖底晶．俄歇电子谱的深度剖面分析显示在所沉积的条件下，底晶中的Ｈｇ向ＣｄＴｅ沉积膜内有较深的扩散．     

添加剂对非晶态Cr电沉积的影响

用Ｘ－射线衍射法（ＸＲＤ）研究了添加剂含量对镀层形成非晶态的影响。测定了非晶态Ｃｒ电沉积的阴极电流效率高达３８％，高于传统镀Ｃｒ溶液。用线性电位扫描研究了非晶态Ｃｒ电沉积的电极过程，并且根据Ａｒｒｈｅｎｉｕｓ公式计算于非晶态Ｃｒ电沉积的表观活化能，研究结果表明，添加剂不仅促使镀层形成非晶态，而且可催化Ｃｒ的电沉积过程。     

微波等离子体化学气相沉积金刚石簿膜

建立了一台微波等离子体化学气相沉积金刚石薄膜的设备。该实验装置由以下几部分组成：微波源及传输系统、反应室、供气系统、真空系统和检测等五部分组成。沉积室是由长７０ｍｍ直径４６ｍｍ的石英管组成的。分别采用ＣＨ４／Ｈ２和ＣＯ／Ｈ２混合气体进行了沉积试验；研究了沉积参数对沉积金刚石膜的影响。在直径３０ｍｍ的单晶硅片和石英片上沉积出了均匀的金刚石膜。采用ＣＨ４／Ｃ２混合气体时，沉积速率在０．５～１．０μｍ／ｈ之间，这与原有的热灯丝方法相近。采用ＣＯ／Ｈ２混合气体时，沉积速率可达到１．７μｍ／ｈ。     

火焰法沉积金刚石薄膜过程中碳在基底中的行为

采用火焰法在Ｍｏ基底上沉积金刚石薄膜，研究了在沉积过程中Ｃ在Ｍｏ基底中的行为，结果表明，在Ｍｏ基层上沉积金刚石时，碳原子与Ｍｏ反应形成Ｍｏ２Ｃ，随时间延长，Ｍｏ２Ｃ层加厚，Ｃ原子扩散进入基底的速率下降，之后Ｃ原子在Ｍｏ２Ｃ层表面达到过饱和开始金刚石形核。     

用CVI工艺制备碳纤维增强C－SiC梯度热结构材料

用化学气相渗（ＣＶＩ）工艺，分别用分段沉积和共沉积方法制取了Ｃ／Ｃ－ＳｉＣ梯度热结构材料，并比较了二者的成分梯度、性能与组织结构特征。     

化学气相沉积碳化钛的热力学和动力学研究

对采用ＴｉＣｌ４－ＣＨ４－Ｈ２反应体系化学气相沉积碳化钛的反应热力学和成核热力学因素进行了分析，并在实验的基础上研究了不同沉积温度下化学气相沉积ＴｉＣ过程的动力学特征，以及在不同的动力学控制机制下气相过饱和度的成核过程对ＴｉＣ涂层的析出形态的影响。在沉积过程中，气相过饱和度和动力学控制机制是控制沉积物的成核过程和析出形态的决定因素。     

旋转CVI制备C/SiC复合材料

旋转 ＣＶＩ是在 ＣＶＩ原理基础上发展的一种制备 Ｃ／ＳｉＣ复合材料的新工艺,通过石墨衬底的旋转,使预制体的制备与基体的沉积同步进行,能有效消除一般ＣＶＩ工艺过程中存在的“瓶颈”效应．在自制的旋转 ＣＶＩ设备上实验,探索了旋转 ＣＶＩ工艺参数中 ＣＨ_３ＳｉＣｌ_３（ＭＴＳ）的流量与浓度、沉积温度和Ｃ布缠绕线速度对ＳｉＣ基体沉积速度,以及沉积温度对基体结构的影响．并在低压（５ｋＰａ）、高温 （１１００℃）、 ４００ ｍＬ·ｍｉｎ^－１ Ｈ_２、 ２００ ｍＬ·ｍｉｎ^－１Ａｒ、 ＭＴＳ４０℃与Ｃ布以１．１～３．５ｍｍ·ｍｉｎ^－１的线速度连续旋转的沉积条件下,实现了单丝纤维间微观孔隙、纤维束之间以及Ｃ布层间宏观孔隙的致密化同步完成．     

SiC薄膜制备工艺进展

本文综述了ＳｉＣ薄膜的制备工艺及进展，介绍了物理气相沉积、化学气相沉积、等离子化学气相沉积及光化学气相沉积等各种ＳｉＣ薄膜的制备方法，简单阐述了各种工艺对薄膜性能的影响，评述了各种制备工艺的优缺点。     

SiC薄膜制备工艺进展

本文综述了ＳｉＣ薄膜的制备工艺及进展，介绍了物理气相沉积、化学气相沉积、等离子化学气相沉积及光化学气相沉积等各处ＳｉＣ薄膜的制备方法，简单阐述了各种工艺对薄膜性能的影响，评述了各种制备工艺的优缺点。     

镍钴离子浓度比对化学镀Co—Ni—P合金工艺的影响

讨论了「Ｎｉ＾２＋」／「Ｃｏ＾２＋」的比值、镀液组成和操作条件对化学镀Ｃｏ－Ｎｉ－Ｐ合金沉积速度的影响。「Ｎｉ＾２＋」／「Ｃｏ＾２＋」的比值越大，沉积速度越快。「Ｎｉ＾２＋」／「Ｃｏ＾２＋」的比值对镀液组成和沉积速度之间的关系有明显影响。当镀液的温度和ＰＨ值较低时，「Ｎｉ＾２＋」／「Ｃｏ＾２＋」的比值对沉积速度的影响我小。     

Synthesis of fluorinated diamond films using a laser technique

A laser chemical vapour deposition process for growing fluorinated diamond thin films on two bearing materials, SiC and 440 C stainless steel, is described. The type of laser, carbon feedstock, laser-precursor gas interactions, and deposition conditions have been established. Raman spectroscopy analysis revealed that the films deposited on SiC consisted of a mixture of diamond and graphite, while the films on 440 C steel were composed of diamond, diamond-like carbon and graphite. The feasibility of diamond formation using laser light-gas interactions is explained.     

Deposition of Diamond Films in a Closed Hot Filament CVD System

A closed system hot filament chemical vapor deposition (CVD) reactor has been used to deposit diamond films on silicon substrates. A fixed charge of hydrogen gas is fed into the deposition system until the desired deposition pressure level is reached. A solid graphite cylindrical rod held above the tungsten filament was the carbon source. System parameters for diamond film growth have been determined. The diamond structure of the films has been verified by x-ray diffraction (XRD). Morphology typical of CVD diamond films has been observed in scanning electron microscopy (SEM). The quality of the diamond films has been evaluated by micro-Raman spectroscopy.     

水冷反应室式MWPCVD制备金刚石膜装置研制

微波等离子体化学气相沉积(MWPCVD)是制备金刚石膜的一种重要方法.为了获得金刚石膜的高速率大面积沉积,研制成功了水冷反应室式MWPCVD制备金刚石膜的装置.装置在微波输入功率为3.0 kW时能长时间稳定运行,并在硅衬底上沉积出金刚石膜.     

Adhesion improvement of diamond films on cemented carbides with copper implant layer

The deposition of diamond films on cemented carbides is strongly influenced by the catalytic effect of cobalt under typical deposition conditions. Decreasing the content of Co on the surface of the cemented carbide is often used for the diamond film deposition. But the leaching of Co from the WC-Co substrate leads to a mechanical weak surface, often causing poor adhesion. In this paper we adopt a copper implant layer to improve the mechanical properties of the Co leached substrate. The copper implant layer is prepared with vaporization. The diamond films are grown by microwave plasma chemical vapor deposition from the CH₄/H₂ gas mixture. The morphology and the quality of the diamond films have been characterized by scanning electron microscopy and Raman spectroscopy. A Rockwell apparatus has evaluated the adhesion of the diamond on the substrate. The results indicate that the diamond films have good adhesion to the cemented carbide substrate due to the recovery of the mechanical properties of the Co depleted substrate after the copper implantation and less graphite formation between the substrate and the diamond film.     

CO2 laser deposition of diamond thin films on electronic materials

Laser-induced pyrolysis has been utilized to create gas-surface chemical reactions necessary for diamond deposition on electronic materials. A 1200 W CO₂ gas laser has been used as an energy source for depositing diamond thin films from a gas mixture of CH₄ and H₂ in a chemical vapour deposition chamber. The substrate temperature was about 500°C. The laser beam energy was largely absorbed by the gases that lead to their excitation and decomposition on contact with the nearby hot substrate. Raman spectroscopy and scanning electron microscope analysis revealed high quality, fine crystalline diamond structures.     

Mechanical properties of diamond thin films

Abstract

The mechanical properties of diamond films deposited via hot filament chemical vapour deposition have been determined using a range of techniques, and related to the composition and morphology of the diamond films as determined by laser Raman spectroscopy. As the quality of the film increases, its hardness (as determined by the volume law of mixtures hardness model) also increases until it is larger than values often reported for polycrystalline bulk material, a consequence of the very small grain size in the films. Coating adhesion, as determined from indentation adhesion tests, also appears to improve with coating quality. Variations in the behaviour of the friction coefficient between diamond films and diamond and steel counterfaces are less well defined, but it appears that the surface morphology of the film is important in dictating the behaviour rather than the quality of the diamond. These results are discussed in the context of the potential use of diamond coatings in tribological applications.

MST/1695     

甲烷浓度对金刚石薄膜质量的影响

纳米金刚石薄膜具有优异的性能,已在多个领域获得广泛应用.但微波等离子体化学气相沉积制备的金刚石薄膜质量却严重受沉积工艺的影响,为了深入了解沉积工艺对制备的金刚石薄膜质量的影响,本文详细研究了甲烷浓度对微波等离子体化学气相沉积( MPCVD)金刚石薄膜质量的影响,利用扫描电镜、X射线衍射、拉曼光谱以及原子力显微镜对其进行...     

液相电沉积金刚石薄膜的研究进展

评述了液相沉积(类)金刚石薄膜的研究现状,介绍了液相合成(类)金刚石薄膜的装置、液态源及薄膜的性能,分析了如何更好地提高(类)金刚石薄膜质量,并在此基础上提出了一种可能制备出高质量金刚石薄膜的脉冲电弧放电沉积装置.     

The versatility of hot-filament activated chemical vapor deposition

In the field of activated chemical vapor deposition (CVD) of polycrystalline diamond films, hot-filament activation (HF-CVD) is widely used for applications where large deposition areas are needed or three-dimensional substrates have to be coated. We have developed processes for the deposition of conductive, boron-doped diamond films as well as for tribological crystalline diamond coatings on deposition areas up to 50 cm × 100 cm. Such multi-filament processes are used to produce diamond electrodes for advanced electrochemical processes or large batches of diamond-coated tools and parts, respectively. These processes demonstrate the high degree of uniformity and reproducibility of hot-filament CVD. The usability of hot-filament CVD for diamond deposition on three-dimensional substrates is well known for CVD diamond shaft tools. We also develop interior diamond coatings for drawing dies, nozzles, and thread guides.Hot-filament CVD also enables the deposition of diamond film modifications with tailored properties. In order to adjust the surface topography to specific applications, we apply processes for smooth, fine-grained or textured diamond films for cutting tools and tribological applications. Rough diamond is employed for grinding applications. Multilayers of fine-grained and coarse-grained diamond have been developed, showing increased shock resistance due to reduced crack propagation.Hot-filament CVD is also used for in situ deposition of carbide coatings and diamond-carbide composites, and the deposition of non-diamond, silicon-based films. These coatings are suitable as diffusion barriers and are also applied for adhesion and stress engineering and for semiconductor applications, respectively.     

金刚石薄膜的性质、制备及应用

金刚石有着优异的物理化学性质，化学气相沉积金刚石薄膜的研究受到研究人员和工业界的广泛关注。通过评述金刚石薄膜的性质、制备方法及应用等方面的研究成果，着重阐述化学气相沉积金刚石薄膜技术的基本原理，分析了各种沉积技术的优、缺点。结合对金刚石薄膜应用的讨论，分析了金刚石薄膜在工业应用中存在的问题和制备技术的发展方向。分析结果表明：MWCVD法是高速率、高质量、大面积沉积金刚石薄膜的首选方法；而提高金刚石的生长速度、降低生产成本等是进一步开发刚石薄膜工业化应用所需解决的主要问题。