制备工艺参数对无氢类金刚石薄膜结构及光学性能的影响

采用射频磁控溅射技术在玻璃基底和单晶硅片上制备了无氢DLC薄膜。采用多种技术手段表征了不同工艺参数下制备的DLC薄膜的结构及光学性能。结果表明,溅射功率、工作气压、基底温度和氩气流量的变化对薄膜结构、透过率和光学带隙有较大影响。薄膜内部sp~3键含量、可见光透过率及光学带隙都随溅射功率或基底温度的增加而减小,随工作气压的增大而增加,随氩气流量的增加先增大后减小。在工作气压为2.0Pa时,可制备出I_D/I_G为0.86、可见光区平均透过率为85%、光学带隙为1.68eV的DLC薄膜。     

基体温度对中频脉冲非平衡磁控溅射技术沉积类金刚石薄膜结构与性能的影响

利用中频脉冲非平衡磁控溅射技术在不同的基体温度下制备了类金刚石(DLC)薄膜,采用Raman光谱、X射线光电子能谱(XPS)、纳米压痕测试仪、椭偏仪对所制备DLC薄膜的微观结构、机械性能、光学性能进行了分析。Raman光谱和XPS结果表明,当基体温度由50℃增加到100℃时,DLC薄膜中的sp3杂化键的含量随基体温度的升高而增加,当基体温度超过100℃时,DLC薄膜中的sp3杂化键的含量随基体温度的升高而减少。纳米压痕测试表明,DLC薄膜的纳米硬度随基体温度的增加先增加而后减小,基体温度为100℃时制备的薄膜的纳米硬度最大。椭偏仪测试表明,类金刚石薄膜的折射率同样随基体温度的增加先增加而后减小,基体温度为100℃时制备的薄膜的折射率最大。以上结果说明基体温度对DLC薄膜中的sp3杂化键的含量有很大的影响,DLC薄膜的纳米硬度、折射率随薄膜中的sp3杂化键的含量的变化而变化。     

FCVA法沉积的超薄类金刚石薄膜的结构与热稳定性

采用FCVA方法沉积了厚度分别为2nm、5nm、10nm和30nm的类金刚石薄膜.在氩气保护下对类金刚石薄膜进行了180、300、400和600℃,保温6h的退火处理.用Raman光谱和宽光谱变角度椭偏仪研究了DLC薄膜的结构和热稳定性.实验结果表明,随着薄膜厚度增大,FCVA法沉积的DLC薄膜中的sp3键含量增加,薄膜热稳定性逐渐改善.当DLC薄膜的厚度为30nm时,薄膜中的sp3键含量达到最高值,薄膜具有最好的热稳定性.当退火温度为600℃时,厚度为2nm和5nm的DLC薄膜结构由非晶态转变为微晶态;厚度为10nm和30nm的DLC薄膜结构发生转变但仍保持非晶态.随着退火温度的升高,各个厚度的DLC薄膜的光学带隙Eg均先增大后减小.     

非平衡磁控溅射制备氮化硅薄膜及其性能研究

采用非平衡磁控溅射技术,通过改变氮气和氩气分压比P(N2)/P(Ar),在钛合金(Ti6Al4V)表面制备出不同结构及性能的氮化硅薄膜.结果显示,制备的氮化硅薄膜为非晶态结构,随着氮气分压的增加,Si-N键的含量增加,其对应的红外吸收峰逐渐变宽,并向高波数偏移.氮化硅薄膜的显微硬度、耐磨性随着P(N2)/P(Ar)的增加而先增加,当P(N2)/P(Ar)为0.25时,随着P(N2)/P(Ar)的增加,薄膜硬度及耐磨性稍有降低.氮化硅薄膜具有较好的膜/基结合力,当增大氮气和氩气分压比,薄膜的脆性随之增加.     

RF-PECVD工艺参数对DLC膜结构及性能的影响

用射频等离子增强化学气相沉积(RF-PECVD)法,在常温下实现在载玻片和单晶硅基片上沉积类金刚石(DLC)薄膜。研究结果表明,工艺参数(功率密度、氩气分压、丁烷分压和极间距)的变化对薄膜硬度和透过率影响较大。薄膜硬度随着功率密度的增加而增加;随着氩气分压或丁烷分压的增加,薄膜硬度降低。薄膜的透过率随着氩气分压先增后减;丁烷分压为0.42～0.7Pa或板极间距为4.5～8cm时,薄膜的透过率均达到90%。     

基片温度对强流脉冲离子束烧蚀等离子体沉积类金刚石薄膜结构和性能的影响

利用强流脉冲离子柬(High-intensity pulsed ion beam-HIPIB)烧蚀等离子体技术在Si(100)基体上沉积类金刚石(Diamond-like carbon-DLC)薄膜，基片温度的变化范围从25℃(室温)到400℃。利用Raman谱、X射线光电子谱(XPS)、X射线衍射(XRD)和原子力显微镜(AFM)研究基片温度对DLC薄膜的化学结合状态、表面粗糙度、薄膜显微硬度和薄膜内应力的影响。根据XPS和Raman谱分析得出，基片温度低于300℃时，sp3C杂化键的含量大约在40％左右；从300℃开始发生sp3C向sp2C的石墨化转变。随着沉积薄膜时基片温度的提高，DLC薄膜中sp3C的含量降低，由25℃时42．5％降到400℃时8．1％，XRD和AFM分析得出，随着基片温度的增加，DLC薄膜的表面粗糙度增大，薄膜的纳米显微硬度降低，摩擦系数提高，内应力降低。基片温度为100℃时沉积的DLC薄膜的综合性能最好，纳米显微硬度22GPa，表面粗糙度为0．75nm，摩擦系数为0．110。     

用RF-PECVD法制备类金刚石薄膜

用射频等离子体增强化学气相沉积(RF-PECVD)法在硅衬底上沉积类金刚石(DLC)薄膜,通过控制甲烷(CH4)与氩气(Ar)流量的比值(VCH4/VAr)分别在上极板和下极板上沉积制备出一系列DLC薄膜,用Raman光谱等检测技术表征了DLC薄膜的结构、表面粗糙度、表面形貌和硬度.结果 表明:随着VCH4/VAr比例...     

NiTi合金生物医用材料表面镀类金刚石薄膜的性能研究

用脉冲电弧离子镀技术在NiTi合金生物材料表面沉积了类金刚石(DLC)薄膜.研究分析结果表明制备的DLC薄膜是四面体非晶碳薄膜;随着DLC薄膜厚度的增加,薄膜的表面粗糙度增加,薄膜中sp3的含量减少;随着sp3含量的增加,薄膜的纳米硬度升高;划痕实验表明临界载荷大于0.9 N.研究得出与NiTi合金相比,DLC薄膜能够有效地降低摩擦系数和磨损.DLC薄膜的摩擦系数主要与薄膜的硬度及薄膜中sp3的含量有关,DLC薄膜的磨损主要是轻微的磨粒磨损及疲劳磨损.     

脉冲真空弧源沉积类金刚石薄膜耐磨特性研究

本文利用脉冲真空弧源沉积技术在Cr17Ni14Cu4不锈钢和Si(100)基体上制备了类金刚石(DLC)薄膜,研究在不同基体偏压下,DLC薄膜的结构与性能.采用拉曼光谱和X射线光电子能谱(XPS)研究DLC薄膜的原子结合状态,利用CSEM销盘摩擦磨损试验机研究其耐磨性,利用HXD1000B显微硬度仪测试其显微硬度,并采用压痕法评价其结合力.研究结果表明:DLC薄膜与基体结合牢固.随着基体偏压的提高,DLC薄膜内sp3键含量增大,薄膜硬度提高.Cr17Ni14Cu4不锈钢表面沉积DLC薄膜后,耐磨性大幅度提高,本文探讨了DLC薄膜的耐磨机理.     

FCVA法制备的超薄类金刚石薄膜的结构分析

用真空阴极过滤电弧(Filtered Cathode Vacuum Arc,FCVA)法制备厚度分别为50 nm,30 nm,10 nm,5 nm,2 nm的类金刚石(DLC)薄膜,利用拉曼光谱和电子能量损失谱研究了薄膜的结构,分析了硬度和内应力的变化趋势。结果表明,随着薄膜厚度的减小,可见光拉曼光谱高斯分解的G峰位置向低波数方向移动,D峰和G峰强度之比Id/Ig不断增大,G峰面积与D峰面积之比Ag/Ad减小;说明随着薄膜厚度的减小,DLC薄膜中的sp3键含量减少,有序化的sp2团簇增加。电子能量损失谱的结果也表明薄膜厚度的减小会引起薄膜中sp3键含量的减少。当薄膜的厚度由50 nm变为30 nm时,薄膜硬度由53.85 GPa减小为39.64 GPa,内应力由4.63 GPa降低为3.47 GPa,随着厚度降低,薄膜的硬度和内应力呈下降趋势。     

Investigation of the microstructure, mechanical properties and tribological behaviors of Ti-containing diamond-like carbon films fabricated by a hybrid ion beam method

Diamond-like carbon (DLC) films with various titanium contents were investigated using a hybrid ion beam system comprising an anode-layer linear ion beam source and a DC magnetron sputtering unit. The film composition and microstructure were characterized carefully by X-ray photoelectron spectroscopy, transmission electron microscopy and Raman spectroscopy, revealing that the doped Ti atoms had high solubility in the DLC films. The maximum solubility was found to lie between about 7 and 13 at.%. When the Ti content was lower than this solubility, the doped Ti atoms dissolved in the DLC matrix and the films exhibited the typical features of the amorphous DLC structure and displayed low compressive stresses, friction coefficients and wear rates. However, as the doped content exceeded the solubility, Ti atoms bonded with C atoms, resulting in the formation of carbide nano-particles embedded in the DLC matrix. Although the emergence of the carbide nano-particles promoted graphitizing due to a catalysis effect, the film hardness was enhanced to a great extent. On the other hand, the hard carbides particles caused abrasive wear behavior, inducing a high friction coefficient and wear rate.     

Adhesion studies of diamond-like carbon films deposited on Ti6Al4V substrate with a silicon interlayer

Diamond-like carbon (DLC) films have proven quite advantageous in many tribological applications due to their low friction coefficient, their extreme hardness, and more recently their high adherence on different substrate materials. However, for many applications, DLC films as thick as 2 μm are required, which cause high residual stress. In order to overcome this problem, this study observed the behavior of different thicknesses of silicon interlayer between DLC films and Ti6Al4V substrates. The study also analyzed the relation of growth parameters to the mechanical properties of DLC films. Silicon and DLC films were grown by using a rf-PECVD at 13.56 MHz with silane and methane atmospheres, respectively. The contribution of an interlayer thickness to the adhesion between the DLC films and Ti6Al4V substrate was evaluated by using a micro-scratch technique. The hardness and friction coefficient were evaluated by using microindentation and lateral force microscopy (LFM), respectively. Raman scattering spectroscopy was used to characterize the film quality. A correlation was found between the intrinsic stress and adhesion of DLC film and the parameters of the silicon interlayer growth. The addition of a silicon interlayer successfully reduced intrinsic stress of the films, even as measured by using a perfilometry technique.     

Characteristics and mechanical properties of titanium-containing diamond like carbon films deposited by cathodic arc evaporation

Depositions of titanium-containing diamond-like carbon (Ti-DLC) films were conducted by mixing C+ and Ti+ plasma streams originated from cathodic arc plasma sources in argon (Ar). The deposition was processed at Ti target current ranging from 20 Amp to 70 Amp. Film characteristics were investigated using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS). Film microstructures were evaluated using field emission scanning electron microscopy (FEGSEM), an atomic force microscope (AFM), X-ray diffractometry (XRD) and high-resolution transmission electron microscopy (HRTEM). Mechanical properties were investigated by using a nanoindentation tester and ball on disc wear test. Results shows that surface roughness (Ra) of the films ranged between 2.4 and 7.2 nm and roughness increased relative to the increase in Ti target current. The FESEM studies showed that the surface micrographs of Ti-DLC films revealed a cauliflower-like microstructure and the cross-sectional micrograph revealed a snake-skin like structure. HRTEM studies showed that the Ti-DLC films consisted of nano scale TiC particles which were comparable with low angle XRD and XPS results. XPS analysis established that the Ti2p spectrum is present when the Ti target current reaches 30 Amp or higher. Ti concentration increased as the Ti target current was increased. An extremely thin TiO2 layer exists on the top of the Ti-DLC films which was comparable with the AES results. The film thickness which could be deposited for Ti-DLC is much higher than that of conventional DLC films. Nanoindentation tests show that the nanohardness of the films ranging 15-22 GPa, with Er values ranging from 145 to 175 GPa. The wear test demonstrates the friction coefficient of the 420SS substrate, DLC and Ti-DLC films were about 0.8, 0.3 and 0.2, respectively. Obviously, the friction coefficients of the Ti-DLC films were lower than that of the DLC films.     

Deposition of diamond-like carbon films by using liquid phase electrodeposition technique and its electron emission properties

We have deposited diamond-like carbon (DLC) films by electrodeposition technique in methanol liquid. XPS showed the films mainly contain carbon. IR spectrum indicated that as-deposited films are hydrogenated carbon films, with the hydrogen mainly bonded to sp³ carbon. Raman measurement suggested that the films consisted of sp³ and sp² carbon. The field emission (FE) property of DLC coated on Si has been measured. The field emission of DLC films started at an applied voltage of 160 V, compared with silicon tip arrays at 600 V, and an emission current of DLC films up to 55 A at 360 V was achieved.     

Deposition of Ti/C nano-composite DLC films by magnetron DC sputtering with dual targets

Deposition of Ti/C nano-composite DLC films by magnetron DC sputtering was examined using dual targets of titanium and carbon, in order to in order to investigate the effects of Ti/C nano-composite structure on its mechanical properties such as hardness or physical properties such as electrical resistivity. The deposition of DLC films or Ti/C nano-composite DLC films was respectively carried out in the atmosphere of argon at the pressure of 0.4 Pa by sputtering of only the carbon target or by co-sputtering of both the carbon one and the titanium one. The DLC film obtained in this study looked semitransparent and dark brown, while the Ti/C nano-composite DLC one looked metallic and light gray. According to Raman spectroscopy, a typical spectrum for DLC was detected for the metal-like titanium containing composite DLC films even though it's intensity was rather small. And it was found that the G band slightly shifted to higher wave numbers and the shoulder D band was enhanced, compared to the spectrum for the DLC films. Furthermore, based on both the indentation hardness and the electrical resistivity of the obtained films, it was assumed that the miniaturization of titanium phase might bring the increase in hardness.     

电化学沉积DLC膜及其表征

采用电化学沉积方法，甲醇有机溶剂作碳源，在直流电源作用下在单晶硅表面沉积得到碳薄膜。薄膜不溶于苯、丙酮等有机溶剂，具有较高的硬度(16GPa左右)，用AFM、Raman和FTIR分析手段对该薄膜表面形貌和结构进行表征，Raman和FTIR结果表明电化学沉积得到的是含氢的类金刚石碳薄膜。通过研究样品薄膜的XPS和XAES谱图特征，进一步证实薄膜是DLC薄膜，并用线性插入法估算出样品薄膜中SP^3的相对含量为60％，同时推测了电化学沉积DLC薄膜的生长机理。     

脉冲偏压对等离子体沉积DLC膜化学结构的影响

以乙炔为气源，用等离子体基脉冲偏压沉积（plasma based pulsd bias deposition缩写PBPBD）技术进行了不同负脉冲偏压条件下制备DLC膜的试验，通过X射线光电子谱（XPS）、激光喇曼光谱[Raman]以及电阻分析方法考察了负脉冲偏压幅值对DLC膜化学结构的影响，结果表明由-50kV到-10kV随负脉冲偏压降低，DLC膜中SP^3键分数单调增加，但当脉冲偏压为0时形成高电阻的类聚合物膜，说明荷能离子的轰击作用形成DLC化学结构的必要条件，键角混乱度和SP^2簇团尺寸与脉冲偏压之间不具有单调关系，在中等幅值负脉冲偏压条件下，键用混乱度较大且SP^2簇团尺寸细小。     

钛离子注入类金刚石碳膜的结构与性能的研究

使用金属离子注入的方法制备了 Ti掺杂的DLC膜。采用原子力显微镜观察了薄膜的表面形貌,Ti掺杂后 DLC 膜的表面粗糙度明显减小,表面光洁度增加,颗粒细化。拉曼光谱分析表明实验获得的薄膜是典型的DLC膜,掺杂Ti后的 DLC膜的拉曼光谱存在明显的肩峰,DLC膜化学结构中的sp2 组分增加,sp3 组分减少。透射电子显微镜分析表明Ti注入后有TiC纳米晶形成。掺入Ti的 DLC膜的硬度从 14GPa增加到 20GPa。Ti 掺杂后的 DLC 膜的摩擦系数(0.15)明显低于未掺杂的DLC膜的摩擦系数(0.21),Ti离子注入有助于提高薄膜的抗磨损性。     

Comparing internal stress in diamond-like carbon films with different structure

Diamond-like carbon (DLC) films with different structures were deposited on Si (100) and stainless steel substrates in a hybrid deposition system with Ar and CH₄ as the feedstocks. The effects of the bias voltage, Ti-interlayer, Ti functional gradient layer and Ti-doping on the internal stress in DLC films were investigated. The results show that the internal stress in DLC films arises from both the intrinsic stress generated during the film growth and the thermal stress generated due to the mismatching of the thermal expansion coefficient between the DLC films and the substrate materials. The intrinsic stress can be released through doping titanium element at the expense of reducing the sp³/sp² ratio. The thermal stress in DLC films can be decreased through introducing Ti-interlayer or Ti functional gradient layer. Noticeably, DLC films with very low internal stress deposited on stainless steel can be obtained through the combination of Ti-doping and Ti functional gradient layer.     

脉冲真空电弧离子镀在不锈钢上沉积类金刚石薄膜的研究

利用脉冲真空电弧离子镀技术在3Cr13不锈钢上制备了类金刚石(DLC)薄膜,通过Raman光谱分析了膜的结构特征,采用摩擦磨损试验机测试了薄膜在不同载荷下的摩擦系数,运用划痕仪研究了膜基的结合强度.结果表明:所镀制的薄膜具有典型类金刚石结构特征,膜中ID/IG为1.33;摩擦系数随着载荷的增大而减小,载荷为5 N,转速120 r/min时的摩擦系数为0.12;Ti过渡层的引入显著地提高了膜基结合力.