AIB用于改进PLD沉积在机械瓣膜上的类金刚石膜的质量

用脉冲激光沉积(PLD)法在热解C制作的人工心脏机械瓣膜上沉积类金刚石(DLC)薄膜,并用3KeV的氩离子轰击(AIB)DLC薄膜。采用拉曼(Raman)光谱和X射线光电子能谱(XPS)分别对AIB前后的DLC薄膜进行检测分析,用光学显微镜观察AIB前后的DLC薄膜表面。实验结果表明:AIB不影响薄膜的黏附性。但是可以在一定程度上导致薄膜微观结构的变化和sp3/sp2比值的提高,可以在薄膜中掺杂微量的Ar元素,可以有效消除薄膜表面吸附的O,但对薄膜中C-O、C=O和COOH的影响较小。因此,离子轰击法可以作为一种改进类金刚石薄膜质量的方法。     

脉冲激光沉积类金刚石膜技术

脉冲激光沉积(PLD)技术制备类金刚石(DLC)薄膜存在着金刚石相含量较低、石墨颗粒多、薄膜与衬底附着力差、膜内应力大等技术难题,为此,研究人员研究出了多种技术措施,如通过引入背景气体、超快激光、偏压、磁场以及加热等措施提高了薄膜金刚石相含量;采用金刚石或丙酮靶材、减小单脉冲能量等措施减少了石墨颗粒;采用间歇沉积、真空退火、超快激光等措施减少了膜内应力;合理没计过渡层改善了膜与衬底间的附着力等.这些技术有力地推动了脉冲激光沉积技术的发展.     

脉冲激光沉积类金刚石膜红外增透技术研究

针对传统方法制备类金刚石(DLC)膜存在的3～5μm波段红外透过率低这一难题,采用飞秒脉冲激光沉积(PLD)法在红外材料硅基底上镀制DLC膜.重点考查了靶材与基片的间距、背景气压、激光单脉冲能量、负偏压、温度以及掺硅量等工艺参数对其透过率的影响,经过大量的实验与优化分析,总结出一套有效的脉冲激光沉积DLC膜工艺来制备优良的光学保护增透膜.相比传统工艺,大大提高了3～5μm波段的平均红外透过率,在硅基底上单面镀制DLC膜的最高红外透过率达到了68.2%,与理论最高值的68.7%仅相差0.5%.     

脉冲激光沉积类金刚石膜和细胞相容性研究

为了解决机械瓣膜的凝血问题,在相同的实验条件下,用脉冲激光沉积(PLD)法在机械瓣膜,Al2O3,316 L不锈钢和Si衬底上沉积类金刚石(DLC)膜.结果表明类金刚石膜与机械瓣膜之间的黏附性最好,用拉曼光谱仪(Raman),X射线光电子能谱仪(XPS)和原子力显微镜(AFM)对机械瓣膜上的类金刚石膜进行检测,然后把人脐带静脉血管内皮细胞(HUVEC)种植在类金刚石膜的表面并进行体外培养.结果表明,Raman光谱的D峰出现在1341.66 cm-1处.G峰出现在1528.17 cm-1处.薄膜中sp3的含量达到21.45%.平均粗糙度为26.4 nm.血管内皮细胞能够正常生长、增殖并融合成片,因此可以实现机械瓣膜表面的血管内皮化,达到抗凝的目的.     

磁场辅助激光沉积类金刚石膜初探

提出了磁场辅助激光沉积类金刚石（DLC）膜技术,在硅基底附近添加磁力线向基底收拢的磁场,用以迫使侧向飞行的离子向基底靠拢并参与成膜。由于离子向基底的集中,使其在膜层中含量大幅上升,间接地减少了大颗粒的比例,因此,与无磁场条件下制备的DLC膜相比,引入磁场不仅提高了DLC膜的沉积速率,而且提高了其机械硬度;更重要的是,间接地证明了激光对靶材离化的高效性,为脉冲激光沉积（PLD）结合磁过滤技术提供了可行性的依据。     

利用脉冲准分子激光在ZnS上沉积类金刚石薄膜

利用氟化氪(KrF)脉冲准分子激光烧蚀沉积(PLD)技术,通过对激光等离子体的粒子成分以及空间分布的诊断,实现了等离子体成分的选择性沉积。在不降低光谱范围和透过率指标的前提下,解决了类金刚石(DLC)薄膜和硫化锌(ZnS)基底的牢固结合问题;通过改进基底平台的扫描方式,在激光烧蚀沉积工艺中沉积了80mm的大面积均匀类金刚石薄膜。制备的类金刚石/ZnS镀膜样品,光谱范围为0.53~12μm,其中1.3~11μm波段透过率在70%以上,膜层均匀性优于95%,可耐受环境湿度95%~100%,工作温度-45~85℃,附着力达到国军标要求。研究表明,利用类金刚石薄膜可以明显提高ZnS材料的耐冲击、耐高温、耐辐射和抗沙粒、盐、雾和尘埃的磨损侵蚀等能力。     

飞秒激光沉积红外窗口类金刚石增透保护膜

脉冲激光沉积法是一种制备类金刚石膜(DLC膜)的新技术.总结了脉冲激光法制备DLC膜在激光源、脉宽、沉积气氛及薄膜掺杂等方面的发展趋势.建立了飞秒脉冲激光沉积DLC膜系统,在不同的沉积条件下(如:真空、氧气氛、掺硅等)开展了实验研究,阐明了不同沉积条件对DLC膜性能的影响规律.在硅、锗红外窗口上镀制了工程实用的DLC增...     

氮气压强对脉冲激光沉积类金刚石薄膜和红外光学特性的影响

为了研究氮气压强对脉冲激光沉积(PLD)类金刚石(DLC)薄膜和红外光学特性的影响,在脉冲激光沉积类金刚石薄膜的实验过程中,把沉积腔抽真空到10-5Pa,再在沉积腔中分别充入10-3、10-2和10-1Pa的氮气来沉积类金刚石薄膜。用拉曼光谱仪和X射线光电子能谱仪(XPS)对类金刚石薄膜的微结构与组成进行检测分析;用原子力显微镜(AFM)对薄膜的表面形貌进行检测分析;用傅里叶变换红外光谱仪(FTIR)对类金刚石薄膜的红外光透射谱进行检测分析。实验结果表明,沉积腔中的氮气压强从10-3Pa增加到10-1Pa时,类金刚石薄膜中sp3键含量增加;C-O和C=O含量减少;石墨晶粒尺寸减小;薄膜表面粗糙度显著增大。与此同时,氮气压强增加还导致类金刚石薄膜对红外光的增透作用减弱、增透范围变窄。     

PLD法制备纳米类金刚石薄膜及衬底温度的影响

利用脉冲激光沉积(PLD)技术在O2氛围下于α-Al2O3(0001)基片上制备出纳米类金刚石薄膜。借助扫描电子显微镜(SEM)、原子力显微镜(AFM)和Raman光谱分析了薄膜的形貌和结构随沉积时衬底温度的变化情况。结果表明：随着衬底温度的升高,薄膜颗粒尺寸减少;在衬底温度为550℃时,所制备的薄膜均匀、光滑,且大约是由14nm大小的颗粒组成。对薄膜的生长机理作出了分析。     

用脉冲激光沉积法制备类金刚石膜及金刚石薄膜

简要评述了用脉冲激光沉积技术制备类金刚石膜及金刚石薄膜的研究进展，总结了激光脉冲沉积制备薄膜的基本原理及其特点，分析了激光波长，能量，衬底温度等对薄膜质量的影响。     

Pulsed laser deposition of titanium nitride and diamond-like carbon films on polymers

We have investigated the deposition of titanium nitride (TiN) and diamond-like carbon (DLC ) films on polymethylmethacrylate (PMMA) substrates using pulsed laser deposition (PLD) technique. The TiN and diamond-like films were deposited by laser ablation (KrF excimer laser λ = 248 nm, pulse duration τ～25 × 10^?9 s, energy density ～2?15J/cm²) of TiN and graphite targets, respectively, at room temperature. These films were characterized by transmission electron microscopy, scanning electron microscopy, x-ray diffraction, Auger electron spectroscopy, UV-visible absorption spectroscopy, and Raman spectroscopy. The TiN films were smooth and found to be polycrystalline with average grain size of 120Å. The diamond-like carbon films were amorphous with a characteristic Raman peak at 1550 cm^?1. The TiN films are highly adherent to the polymer substrates as compare to DLC films. The adhesion strength of DLC films on polymers was increased by interposing thin TiN layer (200Å) on polymers byin-situ pulsed laser deposition. The DLC films were found to be amorphous with good adhesion to TiN/PMMA substrates.     

脉冲激光沉积法沉积类金刚石薄膜的实验研究

为了研究脉冲激光沉积法中衬底温度和距离对类金刚石薄膜的影响,首先温度保持在200℃,靶和衬底间的距离分别取25.0mm和30.0mm来沉积类金刚石膜。其次温度保持在400℃,距离分别取25.0mm和30.0mm来沉积类金刚石膜。用Raman光谱仪对薄膜的微观结构进行检测,用原子力显微镜对薄膜的表面形貌进行检测。实验结果表明：距离增加或者温度升高都会导致类金刚石薄膜的密度和sp3/ sp2的比值减小,薄膜中石墨晶粒的数量增多和体积增大。近距离时温度的变化和低温时距离的变化对薄膜微观结构产生的影响更明显。距离和温度的变化对类金刚石薄膜的表面形貌也产生显著的影响。     

Visible photoluminescence from ZnO/diamond-like carbon thin films

ZnO/diamond-like carbon (DLC) thin films are deposited by pulsed laser deposition (PLD) on Si (111) wafer. Visible room-temperature photoluminescence (PL) is observed from ZnO/DLC thin films by fluorescence spectrophotometer. The Gaussian curve fitting of PL spectra reveals that the broadband visible emission contains three components with λ=508 nm, 554 nm and 698 nm. The origin and possible mechanism of the visible PL are discussed, and they can be attributed to the PL recombination of ZnO and DLC thin films.     

Optical properties of ZnO thin films grown on diamond-like carbon by pulsed laser deposition

ZnO/diamond-like carbon(DLC)thin films are deposited by pulsed laser deposition(PLD),and the room-temperature photoluminescence(PL)is investigated.Using a fluorescence spectrophotometer,we obtain the PL spectra of DLC/Si and ZnO/Si thin films deposited at different substrate temperatures.The ZnO/DLC thin films show a broadband emission almost containing the entire visible spectrum.The Gaussian fitting curves of PL spectra reveal that the visible emission of ZnO/DLC thin films consists of three peaks centered at 381 nm,526 nm and 682 nm,which are attributed to the radiative recombination of ZnO and DLC,respectively.The Commission International de l,Eclairage(CIE)1931(x,y)chromaticity space of ZnO/DLC thin films indicates that the visible PL spectrum is very close to the standard white-light region.     

激光沉积红外窗口高性能类金刚石膜技术

类金刚石(DLC)膜具有宽光谱高透射率、高硬度、高热传导及高稳定性等优点,是红外窗口增透保护膜的优选,但现有方法制备的类金刚石膜难以满足高马赫数或海上盐雾等恶劣条件下的应用。激光法相比其他制备方法具有诸多优点,介绍了激光法制备DLC膜的原理及特点,并分析了实现工程应用的难题及关键技术。采用激光沉积法制备出综合性能优异的类金刚石膜,纳米硬度高达44 GPa、内应力仅0.8 GPa、临界刮擦载荷附着力为59.1 mN。正面镀DLC膜,背面镀普通增透膜的硫化锌、硅、锗等红外窗口的平均透射率达82%~91%。实现了150 mm基片的激光法大尺寸均匀薄膜,膜厚不均匀性≤±2%。制备的DLC膜红外窗口通过军标环境适应性试验,并已实现工程化应用。     

脉冲激光沉积GaN薄膜的研究进展

脉冲激光沉积(PLD)技术凭借其低温生长优势,逐步在GaN薄膜外延领域得到广泛应用。回顾了近年来PLD技术外延生长GaN薄膜的研究进展,包括新型衬底上的GaN薄膜外延研究进展,以及作为克服异质外延的重要手段——缓冲层技术的发展现状。从目前的研究进展可以看出,应用PLD技术制备GaN薄膜及其光电器件具有广阔的发展前景。     

Indium Tin Oxide Thin Films Grown on Polyethersulphone (PES) Substrates by Pulsed‐Laser Deposition for Use in Organic Light‐Emitting Diodes

High quality indium tin oxide (ITO) thin films were grown by pulse laser deposition (PLD) on flexible polyethersulphone (PES) substrates. The electrical, optical, and surface morphological properties of these films were examined as a function of substrate temperature and oxygen pressure. ITO thin films, deposited by PLD on a PES substrate at room temperature and an oxygen pressure of 15 mTorr, have a low electrical resistivity of 2.9×10^?4 Ω cm and a high optical transmittance of 84 % in the visible range. They were used as the anode in organic light‐emitting diodes (OLEDs). The maximum electro luminescence (EL) and current density at 100 cd/m² were 2500 cd/m² and 2 mA/cm², respectively, and the external quantum efficiency of the OLEDs was found to be 2.0 %.