离子束增强沉积制备TiB2薄膜及其性能研究

用离子束增强沉积法（ＩＢＥＤ）在硅及铜基体上沉积了ＴｉＢ２薄膜，研究了轰击离子束能量和束流对薄膜的微结构及力学性能的影响。用俄歇电子谱（ＡＥＳ）分析了膜的成分及其界面状况，用Ｘ射线衍（ＸＲＤ）研究了膜的微结构，并测定了膜的硬度及进行膜的高温氧化试验。结果指出：（１）离子束轰击使薄膜晶化，从而影响到膜的硬度及抗高温氧化性能；（２）离子呸增强的二硼化钛薄膜是一种耐高温氧化的高硬膜。     

掺硼对超纳米金刚石薄膜的影响

采用微波等离子体化学气相沉积(MPCVD)技术,利用氩气、甲烷、二氧化碳混合气体,制备出平均晶粒尺寸在7.480 nm左右,表面粗糙度在15.72 nm左右的高质量的超纳米金刚石薄膜;在此工艺基础上以硼烷作为掺杂气体,合成掺硼的金刚石薄膜.表征结果显示在一定的浓度范围内随着硼烷气体的通入,金刚石薄膜的晶粒尺寸及表面粗糙度增大、结晶性变好,不再具有超纳米金刚石膜的显微结构和表面形态;同时膜材的物相组成也发生改变,金刚石组份逐渐增多,并且膜层内出现了更明显的应力以及更好的导电性能.     

高掺杂Si/BDD薄膜电极的制备及电化学性能

近年来,掺硼金刚石(BDD)膜因具备独特的优异性能而作为电极材料已经受到很大的关注.本文通过MPCVD法在高掺杂硅衬底上生长掺硼金刚石膜,并用四探针、扫描电镜、激光拉曼和电化学工作站对其进行了检测,发现所制备的掺硼金刚石膜电导率达10-2Ω·cm,同时发现金刚石膜质量因硼原子的掺入而有所下降,采用循环伏安法研究其电化学...     

硼掺杂金刚石薄膜电极在酸碱盐中的电化学性质研究

通过热丝化学气相沉积技术,在P型单晶衬底上制备了掺硼金刚石薄膜电极。采用扫描电子显微镜和X射线衍射分析了丙酮流量对硼掺杂金刚石薄膜电极的表面形貌的影响,采用循环伏安法分析硼掺杂金刚石薄膜电极在不同浓度的酸碱盐电解液中的电化学特性。结果表明,硼掺杂金刚石薄膜质量随着丙酮流量的增加而先提高后下降的趋势,并且硼掺杂金刚石薄膜电极在不同电解质中存在不同的电化学窗口,中性溶液中的电化学窗口最宽在3.2 V以上,具有极强的电化学氧化性能。     

气压和偏流对高掺硼金刚石晶体性质的影响(英文)

采用热丝化学气相沉积法,改变工作气压和偏流,在硅基片上沉积了高掺硼金刚石膜。利用扫描电镜(SEM)、拉曼光谱和X射线衍射仪对沉积的金刚石膜表面形貌和结构进行表征。结果显示:当气体压强从3kPa降低到1.5kPa时,金刚石膜有较平的表面形貌和和较好的晶形,薄膜的晶体性质得到良好的改善。但是继续降气体压强,从1.5kPa到0.5kPa时,却呈现出相反的趋势。固定气体压强(1.5kPa),改变偏流,结果表明:适当的偏流(3A)可以改善掺硼金刚石的质量,偏流较高会导致薄膜中非金刚石相增多。     

掺硼金刚石膜的制备及其应用

金刚石虽然具有极为优异的性能,如具有很大的能隙,高的电子迁移率、空穴迁移率和高热导率,以及负的电子亲和势,但要将它用于半导体材料时还不能直接使用,必须要先进行金刚石的P型和n型掺杂。因此,研究金刚石的P型和n型掺杂具有很重要的现实意义。在金刚石薄膜中掺杂时,一般是掺入硼原子以实现P型掺杂,掺入氮原子或磷原子以实现n型掺杂。然而,由于N和P在金刚石中的施主能级太深,现在n型掺杂金刚石薄膜制备尚不成功,这是金刚石实用化的障碍。本文介绍了金刚石膜掺硼目的、方法和制备,总结了掺硼金刚石膜在微电子、电化学、光电子、工具等领域应用状况以及存在问题。     

金刚石薄膜的表面金属化及与Ti薄膜的界面扩散反应的AES研究

利用磁控溅射的方法在金刚石薄膜表面沉积了２５０ｎｍ厚的金属Ｔｉ层，通过３００￣６００℃的真空热处理，促进了Ｔｉ与金刚石之间的界面扩散反应。利用俄歇电子能谱研究了Ｔｉ／金刚石薄膜界面的结合状态，发现在界面上形成了Ｔｉ的碳化物。并发现Ｔｉ与金刚石薄膜发生了大幅度的界面扩散反应，Ｔｉ元素渗入金刚石层达６００ｎｍ，促进了Ｔｉ与金刚石之间形成良好的化学结合，为获得高性能的金刚石切削工具提供了可能。界面扩散反     

掺硼浓度对金刚石薄膜二次电子发射特性的影响

掺硼金刚石薄膜具有负电子亲和势和良好的电子运输性能且容易制备,作为冷阴极材料在图像显示技术和真空技术等领域都存在巨大的应用价值,引起人们的广泛关注。采用MPCVD法利用氢气、甲烷和硼烷的混合气体,制备出不同浓度的掺硼金刚石薄膜。结果表明,掺硼浓度影响金刚石薄膜的物相结构、组织形貌,进而影响其二次电子发射性能,当硼烷的流量为4mL/min时,制备的金刚石薄膜质量最好,二次电子发射系数约为90。     

金刚石薄膜与基材之间过渡层技术的研究

通过ＴＥＭ观察发现在金刚石膜与单晶硅片，金刚石膜与ＡｌＮ陶瓷之间存在一层过渡层，过渡层的存在为金刚石的形核及生长提供了有利的条件，受此启发，为了改善金刚民基材的结合强度，采用磁控溅射，空心离子镀，真空蒸镀等方法在Ｍｏ片上沉积ＴｉＣ，ＴｉＣＮ（Ｃ／Ｎ＝１／２）ＴｉＣＮ（Ｃ／Ｎ＝１／１０）等薄膜，研究了它们对金刚石膜与基材的结合强度的影响。     

非晶硅太阳电池窗口层材料掺硼非晶金刚石的研究

以固态掺杂方式利用过滤阴极真空电弧技术制备掺硼非晶金刚石薄膜, 获得性能优良的宽带隙p型半导体材料, 再利用等离子增强化学气相沉积技术制备p-i-n结构非晶硅太阳电池的本征层和n型层, 最终制成以掺硼非晶金刚石薄膜为窗口层的非晶硅太阳电池. 利用Lambda950紫外-可见光分光光度计表征薄膜的光学带隙, 并测试电池开路电压、短路电流、填充因子以及转化效率等参数, 再分析电池的光谱响应特性. 实验表明, 掺硼非晶金刚石薄膜的光学带隙(～2.0eV)比p型非晶硅更宽, 以掺硼非晶金刚石薄膜用作非晶硅太阳电池的窗口层, 能够改善电池的光谱响应特征, 并提高转化效率达10%以上.     

表面镀钛对金刚石薄膜场发射特性的影响

利用等离子体化学气相（MWPCVD）沉积法在Si（100）面上沉积了金刚石薄膜,采用SEM、AFM、XRD、Raman、XPS等方法对薄膜的结构及表面形貌进行了分析。为提高薄膜的场发射性能,在金刚石表面溅射了金属Ti,对比金刚石薄膜、金刚石／金属Ti复合薄膜的场发射性能,结果表明,金刚石／金属Ti薄膜的发射电流密度更大,且随着电场的增加电流密度急剧增加,开启电场低,约为3V／μm,当电场为25V／μm时发射电流密度可达到1400mA／cm2,并在机理上进行了一些探索,对金刚石／金属复合结构薄膜的场发射性能研究有重要意义。     

Growth of polycrystalline and nanocrystalline diamond films on pure titanium by microwave plasma assisted CVD process

Well-faceted polycrystalline diamond (PCD) films were deposited along with nanocrystalline diamond (NCD) films on the pure titanium substrate by a microwave plasma assisted chemical vapor deposition (MWPCVD) system in the environment of CH₄ and H₂ gases at a moderate temperature. Diamond film deposition on pure titanium and Ti alloys is always extremely hard due to the high diffusion coefficient of carbon in Ti, the big mismatch in their thermal expansion coefficients, the complex nature of the interlayer formed during diamond deposition, and the difficulty of attaining very high nucleation density. A well-faceted PCD film and a smooth NCD film were successfully deposited on pure Ti substrate by using a simple two-step deposition technique. Both films adhered well. Detailed experimental results on the preparation, characterization and successful deposition of the diamond coatings on pure Ti are discussed. Lastly, it is shown that smooth NCD film can be deposited at moderate temperature with sufficient diamond quality for mechanical and tribological applications.     

Study of carbide-forming element interlayers for diamond nucleation and growth on silicon and WC-Co substrates

Diamond nucleation and growth on several typical carbide-forming elements (CFE) (Ti, Cr and W) coated Si and WC-Co substrates were studied. The ion beam sputtered CFE interlayers show an amorphous/nanocrystalline microstructure. The diamond formed on the CFE coated substrates shows higher nucleation density and rate and finer grain structure than on uncoated substrates. Consequently, nanocrystalline diamond thin films can be formed on the CFE coated substrates under conventional microcrystalline diamond growth conditions. Among the three tested CFE interlayers, diamond has the highest nucleation density and rate on W layer and the lowest on Ti layer. The diamond nucleation density and rate on CFE coated WC-Co are much higher than those on widely used metal nitride coated WC-Co.     

Energetics of Ti atom diffusion into diamond film

Energetics of Ti atom in metallization of diamond film were studied by calculations using density functional theory (DFT) and a composite basis set. Cluster models consisting of more than 10 C atoms were chosen to simulate the diamond phase with their boundaries saturated with H atoms. When Ti atom diffuses from the surface into the bulk of diamond interstitially, the energy barriers were found to be about 40 eV. Ti was found to favor substitutional sites rather than interstitial sites in diamond crystal. Our results indicate that the high concentration of Ti in chemical vapor deposited diamond films after metallization would occupy the grain boundaries rather than the bulk of diamond grain.     

衬底表面预处理对金刚石薄膜形核及长大的影响

用燃烧火焰法在 TC4 Ti 合金和单晶 Si(001)面上沉积了金刚石薄膜。对合成的膜进行了扫描电镜、激光喇曼光谱分析。结果表明,金刚石薄膜的结构和形貌强烈取决于沉积温度、O_2/C_2H_2流量比等工艺参数。研究了衬底表面预处理对金刚石薄膜形核及长大的影响,并对表面预处理影响形核的原因进行了初步探讨。     

金刚石膜上电子束蒸镀Ti/Ni/Au多层膜

经过相图分析提出了CVD金刚石膜上蒸镀Ti/Ni/Au的体系。采用该体系、富氧预处理工艺和电子束真空镀膜方法 ,金刚石膜和多层金属膜之间获得了良好结合强度。研究发现 :富氧预处理对多金属膜和金刚石膜之间的结合强度影响显著。进一步利用俄歇电子能谱 (AES)证实 :C向Ti中扩散层有 15 0nm之多 ,并出现了厚度约为 90nm稳定含量层 ,说明有确定化学比的反应产物生成 ;富氧处理在金刚石膜与Ti金属层之间增加了氧的含量 ,为形成TiO和TiC提供了合适的条件。     

金刚石表面的Ti、Mo、W镀层及界面反应对抗氧化性能的影响

为了提高工业金刚石的抗氧化能力,本文用XRD、SEM、DTA和TGA等方法研究了Ti、Mo、W镀层与金刚石界面反应过程、结构特征及对金刚石抗氧化性能的影响.结果表明:Ti在高于600℃、Mo在高于650℃、W在高于650℃与金刚石界面发生固相反应,通过反应扩散过程在金刚石表面外延生长成相应的TiC、MoC+Mo₂C及WC+W₂C碳化物层.该致密连续的碳化物层具有较高的抗氧化能力,延缓了金刚石表面的氧化.镀Ti、Mo、W金刚石在空气中的氧化温度达958℃、871℃和880℃.Ti、Mo、W镀层经真空碳化处理后,抗氧化温度分别达1024℃、977℃和986℃.而未镀金刚石在780℃以上即开始氧化.     

Nanoindentation and AFM studies of PECVD DLC and reactively sputtered Ti containing carbon films

Amorphous carbon film, bdalso known as DLC film, bdis a promising material for tribological application. It is noted that properties relevant to tribological application change significantly depending on the method of preparation of these films. These properties are also altered by the composition of the films. In view of this, bdthe objective of the present work is to compare the nanoindentation and atomic force microscopy (AFM) study of diamond like carbon (DLC) film obtained by plasma enhanced chemical vapour deposition (bdPECVD with the Ti containing amorphous carbon (Ti/a- C : H) film obtained by unbalanced magnetron sputter deposition (UMSD). Towards that purpose, DLC and Ti/a- C : H films are deposited on silicon substrate by PECVD and UMSD processes, respectively. The microstructural features and the mechanical properties of these films are evaluated by scanning electron microscopy (SEM), bdtransmission electron microscopy (TEM), nanoindentation and by AFM. The results show that the PECVD DLC film has a higher elastic modulus, hardness and roughness than the UMSD Ti/a- C : H film. It also has a lower pull off force than Ti containing amorphous carbon film.     

采用钛-铝-钼过渡层在铜基底上沉积金刚石薄膜的研究

采用钛-铝-钼过渡层研究了铜基片上金刚石薄膜的化学气相沉积.用SEM和Raman谱研究了薄膜的形貌和质量.用XRD分析了膜基间形成的化合物的成分,并进一步分析了铝的存在对膜基结合力的影响.实验证明,钛-铝-钼过渡层的存在显著提高了金刚石薄膜与铜基底的结合力.