PECVD法低温沉积SiGx薄膜的防水汽扩散性能研究

外界水汽和离子的扩散对集成电路和传感器等器件的性能及使用寿命有很大影响，利用无机钝化材料阻挡水汽和离子的扩散是常用的提高器件寿命和稳定性和方法。本文采用ＰＥＣＶＤ方法在较低的衬底温度条件下沉积碳化硅薄膜，利用各种方法研究了碳化硅薄膜的防潮性能。实验证明，碳化硅薄膜是一种良好的水汽扩散阻挡材料，其防潮能力达到甚至超过了集成电路生产中常用的氮化硅薄膜。并且，低温碳化硅薄膜具有非常好的化学稳定性和抗刻蚀     

PECVD法低温淀积SiCx薄膜的防水汽扩散性能研究

外界水汽和离子的扩散对集成电路和传感器等器件的性能及使用寿命有很大影响，利用无机钝化材料阻挡水汽和离子的扩散是常用的提高器件寿命和稳定性的方法。本文采用PECVD方法在较低的衬底温度条件下淀积碳化硅薄膜，利用各种方法研究了碳化硅薄膜的防潮性能。实验证明，碳化硅薄膜是一种良好的水汽扩散阻挡材料，其防潮能力达到甚至超过了集成电路生产中常用的氮化硅薄膜。并且，低温碳化硅薄膜具有非常好的化学稳定性和抗刻蚀能力，在各种微加工工艺中有广泛的应用前景。     

正交实验方法研究PECVD碳化硅薄膜的防水汽扩散性质

利用正交实验设计，研究了碳化硅薄膜的防水汽扩散性质。通过测试水汽在碳化硅薄膜中的扩散速率，初步确定了四种沉积参数影响碳化硅薄膜防水汽扩散能力的规律。实验发现，射频频率的变化对碳化硅薄膜的防水汽扩散能力的影响最大，气体流量比次之，而功率和气体压力的变化影响较小。     

碳化硅薄膜热敏材料的制备

本文介绍了采用硅、碳复合靶射频溅射镀制碳化硅薄膜。用四探针法分别测得了在不同氩气分压下,不同溅射功率与基板温度下,电阻率与温度关系曲线。用 NP-1型光电子能谱仪测量薄膜成分。结果表明在不同的溅射条件下,制备的碳化硅薄膜属于硅、碳、碳化硅混合成分的薄膜,其电阻率相差很大。本工艺制备的碳化硅薄膜,在所测量的0～300℃温区内,具有明显的负温度系数。     

原位合成TiB_2-SiC基复合材料

碳化硅材料具有许多优良的性能，采用原位合成碳化硅基复合材料已经成为当前研究的一大热点。本文对近年来采取原位合成ＴｉＢ２来增强增韧碳化硅基复合材料作了简要综述。     

蓝宝石衬底异质外延碳化硅薄膜反应机理研究

对宽禁带半导体材料碳化硅薄膜的异质外延工艺和反应机理进行了讨论，针对实验使用常压水平卧式反应室，分析了生长过程中气流流速分布、反应室内温度分布以及反应气体浓度分布，指出“汽相结晶”过程对薄膜生长区Si/C比例有很大影响，从而影响了碳化硅薄膜的生长速率，在SiC薄膜的生长过程中，对Si/C原子比例的控制一直是影响薄膜表面形貌和膜层掺杂浓度的重要因素。这很好地解释了薄膜生长过程中出现的异常现象。     

PECVD法低温淀积SiC_x薄膜的防水汽扩散性能研究

外界水汽和离子的扩散对集成电路和传感器等器件的性能及使用寿命有很大影响 ,利用无机钝化材料阻挡水汽和离子的扩散是常用的提高器件寿命和稳定性的方法。本文采用PECVD方法在较低的衬底温度条件下淀积碳化硅薄膜 ,利用各种方法研究了碳化硅薄膜的防潮性能。实验证明 ,碳化硅薄膜是一种良好的水汽扩散阻挡材料 ,其防潮能力达到甚至超过了集成电路生产中常用的氮化硅薄膜。并且 ,低温碳化硅薄膜具有非常好的化学稳定性和抗刻蚀能力 ,在各种微加工工艺中有广泛的应用前景。     

双热源合成碳化硅过程的三维数值模拟及窑炉结构优化设计

采用CFD软件,选取热电耦合模型、组份传输反应模型与辐射模型。对碳热还原合成碳化硅过程中双热源合成炉内能量及物质传递过程进行模拟研究。将模拟结果与工业试验数据进行对比验证,从而验证了模拟的可靠性,揭示了碳化硅合成过程中的传热传质机理。根据分析结果对传统的双热源碳化硅合成炉进行结构优化设计,对于延长合成炉的使用寿命、提升产品质量、改善工况具有一定的指导意义。     

双热源合成碳化硅过程的三维数值模拟及窑炉结构优化设计北大核心CSCD

采用CFD软件,选取热电耦合模型、组份传输反应模型与辐射模型。对碳热还原合成碳化硅过程中双热源合成炉内能量及物质传递过程进行模拟研究。将模拟结果与工业试验数据进行对比验证,从而验证了模拟的可靠性,揭示了碳化硅合成过程中的传热传质机理。根据分析结果对传统的双热源碳化硅合成炉进行结构优化设计,对于延长合成炉的使用寿命、提升产品质量、改善工况具有一定的指导意义。     

PCVD法对碳化硅陶瓷的表面改性研究

利用等离子辉光放电化学气相沉积技术（ＰＣＶＤ），控制甲烷与磋烷质量流量比、硅烷与氨质量流量比，在碳化硅基体表面分别沉积上无定形碳化硅和氨化硅薄膜，研究其膜的组成、沉积工艺、厚度等对碳化硅陶瓷的强度改性影响．在一定的沉积条件下沉积的碳化硅薄膜可以使基体强度提高２０％达到８５０ＭＰａ，沉积氮化硅薄膜使强度提高３０％达到９００ＭＰａ，改性的效果很明显．     

用溶胶－凝法制备锆钛铅铁电薄膜

利用溶胶－凝胶法在镀铂硅片上制备了ＰＺＴ铁电薄膜。利用ＸＲＤ、ＳＥＭ和ＴＥＭ观察了ＰＺＴ薄膜的组成与形貌，测定ＰＺＴ薄膜的电学性能。为防止薄膜发生龟裂，在前体溶液中加入了干燥控制化学添加剂，并采用慢速变温的热处理过程。ＰｂＴｉＯ３过渡层保证了ＰＺＴ薄膜结晶完好。     

Structural and electrical studies of thermally evaporated nanostructured CdTe thin films

CdTe thin films were deposited on KCl and glass substrates using thermal evaporation technique under high vacuum conditions. CdTe bulk compound grown by vertical directional solidification (VDS) technique was used as the source material to deposit thin films. Powder X-ray diffraction technique was employed to identify the phase of the as grown bulk CdTe compound as well as its thin films. Surface morphology and the stoichiometry of the bulk compound and thin films was carried out by using scanning electron microscope (SEM) with an attachment of energy dispersive spectrometer(EDS). Microstructural features associated with the as deposited CdTe thin films were studied by using transmission electron microscope (TEM). The films deposited on to glass substrates at different temperatures have been used to study the I-V characteristics of the films. These parameters have been studied in detail in order to prepare good quality nanostructured thin films of CdTe compound. CdTe bulk compound grown by VDS method and its thin films prepared by thermal evaporation method found to have single phase with cubic structure. Size of the particles in the as deposited films vary between 5 and 40 nm In the present study efforts have been made to correlate the electrical and optical properties of the CdTe thin films with the corresponding microstructural features associated with them.     

金刚石薄膜涂层硬质合金刀具的界面表征

采用SEM对金刚石薄膜涂层硬质合金刀具的金刚石薄膜表面、背面及金刚石薄膜剥落后的硬质合金刀片表面的典型形貌进行了观察,并采用TEM对金刚石薄膜／硬质合金刀片横截面的微观组织进行了研究,还采用FT—Raman光谱法对金刚石薄膜表面及金刚石薄膜剥落后的硬质合金刀片表面的微观结构进行了表征．结果表明：经适当的化学侵蚀脱钻和等离子体刻蚀脱碳预处理后,金刚石薄膜涂层硬质合金刀具的界面通常存在薄的（数十nm）石墨碳层;局部区域见到金刚石粒子直接生长在WC颗粒上,金刚石膜／基横截面的典型组织层次为：金刚石薄膜／薄的石墨碳层／细小的WC层／残留的脱碳层（η相＋W相）／原始的硬质合金基体．     

Chemically deposited nickel oxide as counter electrode for dye sensitized solar cell

Nickel oxide (NiO) thin films have been synthesized by simple and inexpensive chemical bath deposition at low temperature. The synthesized thin films were annealed at 623 K and used for further characterization. Structural and morphological properties of the NiO thin film were characterized using X-ray diffraction and scanning electron microscope (SEM), respectively. The structural study shows the simple cubic formation of NiO thin films with average crystallite size of 9 nm. Honeycomb like surface morphology with porous structure was observed from the SEM study. NiO thin film electrode has been used as a counter electrode in dye sensitized solar cell. Finally, photovoltaic parameters such as short circuit current density (J_sc), open circuit voltage (V_oc), Fill Factor (FF) and efficiency (η) have been studied.     

锐钛矿型TiO2胶体制备抗菌陶瓷的特性研究

利用锐钛矿晶型的纳米TiO2 胶体溶液 ,将硅胶作为粘结剂按不同配比加入TiO2 胶体 ,用提拉法在陶瓷表面形成均匀薄膜并在高温下烘烤成膜。研究TiO2 和硅胶在不同比例情况下的薄膜特性 ,讨论了退火温度对亲水性及光催化活性的影响 ,利用分光光度计测量了TiO2 薄膜对亚甲基蓝的分解活性 ,测定了薄膜对洗涤剂、消毒剂、3 %NaOH和沸水的抗腐蚀能力。结果表明 ,利用这种方法制备的薄膜具有较好的光致亲水性和光催化性 ,并具有良好的抗腐蚀能力。     

Development and characterization of thin polymer films relevant to fiber processing

Dilute solutions of cellulose, polypropylene, polyethylene, nylon and polyester were spun cast onto gold and silica wafers to generate thin films of these polymers, which are commonly used in the manufacture of synthetic fibers. The thin films were used as substrates in the quartz crystal microbalance and nano-indentation techniques to monitor adsorption and friction behaviors after treatment with a polymer solution (as a mimic of a textile finish). The spin coating conditions were optimized in terms of the resulting film morphology, thickness and surface energy. Atomic force microscopy, X-ray photoelectron spectrometry, ellipsometry and contact angle were used to probe the physical and surface properties of the resulting films. Overall, we developed thin films that are helpful to inquire, at the molecular level, phenomena relevant to fiber and textile processing including swelling, degradation, and adsorption of polymers and surfactants.     

（Ba0.6Sr0．4）Ti1-xZnxO3薄膜的介电调谐性能

利用溶胶-凝胶法在Pt／TiO2/SiO2/Si衬底上制备了（Ba0．6Sr0．4）Ti1-xZnxO3（BSTZ）薄膜,用X射线衍射和扫描电镜分析测定了BSTZ的微结构和薄膜的表面形貌,研究Zn掺杂量对其介电调谐性能的影响,结果表明,随Zn含量的增加BSTZ物相无明显变化,其介电常数、调谐量先增加后降低,但介电损耗却先降低后增加。在室温1MHz下,1．5m01％Zn掺杂BSTZ薄膜有最大的调谐量54．26％;2．5mol％Zn掺杂BSTZ薄膜有最低的介电损耗0．0148和最大的优值因子30．3。     

Stable deposition of silicon oxynitride thin films with intermediate refractive indices by reactive sputtering

The deposition stability of silicon oxynitride thin films with intermediate refractive indices was investigated as a function of argon concentration in the process gas mixture. The silicon oxynitride thin films were deposited by pulsed dc reactive magnetron sputtering in a mixture of argon, nitrogen and oxygen. The refractive indices of the silicon oxynitride thin films gradually decreased with oxygen percentage in the reactive gas mixture when high argon concentrations were used. It is proposed that many silicon atoms were sputtered from the target and reached the substrates in high argon concentrations; consequently, drastic oxidation of the thin films did not occur.     

碳化硅薄膜制备方法及光学性能的研究进展

碳化硅薄膜有密度小、热导率高、热膨胀系数低、硬度高等优异的性能。介绍了制备碳化硅薄膜的2种常用方法。即化学气相沉积和磁控溅射技术,比较了2种方法的各自优势。总结了碳化硅薄膜光学性能及短波发光特性的研究进展。