硼掺杂微晶硅薄膜的椭圆偏振光谱分析

采用射频等离子体增强化学气相沉积(radio frequency plasma enhanced chemical vapor deposition,RF-PECVD)技术在玻璃衬底上沉积了硼掺杂微晶硅薄膜。采用椭圆偏振光谱和Raman光谱分析了辉光功率和硼掺杂量对薄膜的晶化率、表面粗糙度、空隙率和非晶孵化层厚度的影响。结果表明:随着输入功率的增加,薄膜表面粗糙度的变化趋势为先缓慢减小、再快速增加、然后再次减小;沉积薄膜中的体层晶化率和空隙率的变化趋势相同,而空隙率与非晶孵化层厚度的变化趋势相反。随着初始硼掺量的增加,薄膜表面粗糙度的变化趋势为先缓慢增加、再减小、然后再增加;沉积薄膜的体层晶化率和空隙率并没有类似的对应关系。此外,对RF-PECVD沉积硼掺杂微晶硅的生长机理进行了分析。     

纳米晶硅多层薄膜的低温调控及其发光特性

采用单-双靶交替溅射法低温沉积了纳米晶硅多层薄膜（nc-SiO_x/a-SiO_x）,通过改变a-SiO_x势垒层的厚度和化学成分比例,实现了纳米晶硅多层薄膜的低温过程控制。透射电子显微镜（TEM）结果显示,a-SiO_x层太薄,不能有效阻断纳米硅生长,导致多层周期结构在后期沉积过程中受到破坏;增加a-SiO_x层厚度,周期性结构生长得以实现,但仍有部分纳米硅穿透a-SiO_x势垒层;傅里叶变换红外光谱（FTIR）分析表明,薄膜中的氧化反应以及活性氢对物相分离过程的促进作用均对纳米硅生长有影响。进而增加a-SiO_x层氧含量,纳米硅的纵向生长被成功阻断。在此基础上,通过调整nc-SiO_x层厚度实现了薄膜光学带隙调整和纳米硅粒度控制。光吸收谱分析显示,随nc-SiO_x层厚度的增加,薄膜光学带隙逐渐减小;光致发光谱表明,多层周期结构实现了纳米硅尺寸的调控,粒子尺寸为几个纳米的纳米硅表现出了较强的发光,发光机制为量子限制效应-缺陷态复合发光。     

离子束增强沉积制备p-ZnO薄膜

采用离子束增强沉积技术制备了ZnO薄膜,分析了退火温度、退火气氛对所制备ZnO薄膜的结构、电学特性和发光特性的影响。利用IBED法获得的薄膜p型N-In共掺ZnO薄膜在氮气下退火,随着退火温度的升高,薄膜电阻值先降低后升高,然后再降低。而在氧气下退火,即使退火温度只有400℃,薄膜的电阻很快变大。     

退火温度对溅射法沉积Cu-Cr-O薄膜性能的影响

使用Cu Cr O2陶瓷靶材,利用射频磁控溅射方法在石英衬底上沉积了Cu-Cr-O薄膜,研究了退火温度对Cu-Cr-O薄膜结构及光电性能的影响。X射线衍射分析显示,退火温度为973 K时薄膜即已晶化并形成单相铜铁矿结构CuCrO2,随着退火温度的升高,薄膜结晶性逐渐提高。紫外-可见光谱与电学性能测量结果表明:薄膜可见光透过率随退火温度升高呈上升趋势,电导率则呈下降趋势,在973～1273K退火薄膜的可见光透过率最高为50%,电导率最高为0.12 S/cm。扫描电子显微镜照片显示,Cu-Cr-O薄膜电导率的下降主要与退火产生的微裂纹有关。     

退火温度对原子层沉积TiO2薄膜结构、形貌和光学性能影响

采用原子层沉积技术(ALD)在石英衬底上制备了TiO₂薄膜,并对其进行不同温度的快速光热退火处理。采用X射线衍射仪(XRD)、拉曼(Raman)光谱、扫描电子显微镜(SEM)、原子力显微镜(AFM)和紫外-可见分光光度计(UV-Vis)对薄膜进行表征。研究了退火温度对薄膜结构、表面形貌和光学性能的影响。结果表明：当薄膜未退火时,其具有非晶态性质;薄膜在300～600℃的范围下退火时,其具有结晶态性质。当样品在未退火下,其表面粗糙度和光学带隙分别为17.226 nm和3.57 eV;随着退火温度不断升至600℃时,薄膜的表面粗糙度增至30.713 nm变大,晶粒尺寸增至24.75 nm,光学带隙减至3.41 eV。此外,样品的折射率和消光系数随着退火温度的升高呈下降趋势。在实验条件下,最佳退火温度为600℃。     

不同退火温度In掺杂ZnO薄膜的表面形貌和光学性质

用X射线衍射仪(XRD)、扫描电子显微镜(SEM)和紫外-可见分光光度计观察4%(原子分数)In掺杂ZnO薄膜的微结构、表面形貌和光学性质.微结构分析表明:薄膜仍为六角纤锌矿结构,由于In杂质的掺入,使得薄膜结晶度劣化,退火温度对薄膜微结构影响较小;表面形貌观察结果显示:薄膜表面凹凸不平,450 ℃退火处理薄膜表面最平坦,尺寸在50～100 nm之间小颗粒致密、均匀地分布于起伏的表面;紫外可见透射谱研究结果表明:随着退火温度升高,薄膜光学带宽E_g由3.267 eV减小到3.197 eV,该结果可能与薄膜表面残余应力发生变化密切相关.     

退火和老化气氛对铝酸钙玻璃上SiO_2薄膜性能影响

将用IAD法在CAB玻璃基体上沉积的SiO_2薄膜在600℃条件下部分进行退火,然后在不同湿度气氛中进行老化处理.利用分光光度计、纳米硬度计和扫描电镜研究了退火处理及不同老化气氛对SiO_2薄膜的光谱性能、硬度及摩擦性能的影响.实验结果如下:虽然退火和老化方式影响SiO_2薄膜的结构,但不同处理的SiO_2膜层表面摩擦系数均小于CAB玻璃基体,退火处理后的SiO_2薄膜硬度高于不退火处理的SiO_2薄膜硬度;SiO_2薄膜在可见光区内对CAB玻璃能够起到有效的增透作用;退火处理后红外透过率提高.实验结果表明CAB玻璃表面镀SiO_2薄膜在不损害光谱性能的同时可以起到有效地防护作用,显著提高其耐摩性能.     

退火处理对玻璃表面沉积的ZnO薄膜微观形貌与性能的影响

以Zn(NO3)2·6H2O为前驱体,采用超声喷雾热解法在500℃下、在钠钙硅浮法玻璃衬底上制备了ZnO薄膜.分别在不同温度(500、550、600℃)和不同时间(30、60、120min)对制备的ZnO薄膜进行了退火处理.研究退火条件对ZnO薄膜微观结构、形貌以及光学性能的影响.结果表明:退火处理能提高ZnO薄膜的c轴取向;随着退火时间的延长,ZnO薄膜附着强度随之增加,但c轴取向度呈先增强,至120min时又开始呈下降的趋势;随着退火温度的升高,ZnO薄膜的c轴取向亦出现先显著增强,之后又开始下降的趋势,同时可见光透过率亦呈相同的变化趋势.最佳退火条件为500℃温度保温60min,此时薄膜不仅c轴取向生长优势明显,结晶质量良好,表面颗粒大小均匀,致密平滑,同时薄膜的可见光透过率由退火前的70％提高到90％.     

整体低温退火热处理法在4000m^3球罐施工中的应用

介绍整体低温退火热处理法的工艺原理及其在中原化肥厂２台４０００ｍ＾３薄壁大型氨球罐焊后消除焊接残余应力中的应用。     

Low Temperature Chemical Vapor Deposition of Aluminosilicate Thin Films on Carbon Fibers

We report the deposition of aluminum oxide and aluminosilicate thin films onto carbon fiber substrates, at temperatures of 200° and 250°C, respectively. For aluminosilicate films, the Al/Si ratio of the resultant film varied concomitantly with the composition of the liquid precursor mixture. The growth rate for the oxide films was 15–17 Å/min, comparable with other methods carried out at higher temperatures. Cross-section SEM images indicate that the deposited films are conformal, following the complex topography of the carbon fiber substrate. Preliminary gas-phase IR analysis suggests that the coatings decompose the nerve agent simulant dimethyl methylphosphonate at temperatures as low as 35°C, suggesting the utility of the reported methodology for the design/fabrication of actively protective fabrics and clothing.     

Polymer Functionalization and Thin Film Deposition by Remote Cold Nitrogen Plasma Process

Modification of polymer surfaces by cold plasma processes is attracting a growing interest. Especially, the use of plasma gases such as N₂, O₂ or air, which are cheap and environmentally safe, is very attractive from an industrial point of view. The lifetime of atomic oxygen being very short, it is very difficult to operate with air or oxygen plasma when wide plasma volume is required. However, it is possible to obtain cold remote nitrogen plasma reaching volume of several m³ due to the long lifetime of atomic nitrogen because of a re-dissociation mechanism. Moreover, the temperature being close to the ambient makes this plasma very attractive for functionalization and/or coating of polymer surfaces. Several applications of this plasma process are presented in this paper. The incorporation of new chemical functions during the treatment of polymers leads to an increase of their adhesion properties. Several industrial applications (painting, sticking, bonding, foaming and thermo-covering) are presented. The ability of this remote plasma to decompose, to polymerize, or to react with a volatile chemical component is described through three examples involving polymer substrates: (i) the deposition of metallic films; (ii) the synthesis of a nitride film combining hardness and elastic behavior; (iii) the synthesis of an organosilicon film showing interesting barrier properties. Adhesion aspects are investigated for all these examples.     

高低温冲击试验对漆膜附着力的影响

考察了不同基材上常用底漆、复合涂层的附着力,进行高低温冲击试验后,再次测试了漆膜附着力,考察了高低温冲击试验对漆膜附着力的影响,为以后根据环境要求选用油漆提供数据支持。     

PECVD制备富硅氮化硅薄膜的工艺条件及其性质的研究

采用等离子体增强化学气相沉积法(PECVD)以SiH4和N2为反应气体,分别在射频功率、硅烷稀释度[SiH4/N2]、衬底温度为变量的情况下制备了富硅氮化硅薄膜材料,利用X射线衍射谱(XRD)、傅里叶变换红外谱(FTIR)、紫外-可见光吸收谱(UV-Vis)对薄膜材料进行了表征,并研究了薄膜材料的微结构和晶化状况、光学特性等.实验结果表明,所沉积薄膜都为富硅的非晶氮化硅材料,改变射频功率、硅烷稀释度和衬底温度可以控制氮化硅薄膜中N元素的含量、光学带隙的大小和薄膜的折射率,并制备出最适宜富硅氮化硅薄膜,为进一步退火析出硅量子点奠定了基础.     

氮化硅薄膜制备方法现状综述

氮化硅薄膜是一种多功能材料，在许多领域有着广泛的应用。本文系统综述氮化硅薄膜的性质、结构、应用及各种制备方法，并对今后的研究作了展望。     

Electron Cyclotron Resonance Plasma-Enhanced Metalorganic Chemical Vapor Deposition of Tantalum Oxide Thin Films on Silicon near Room Temperature

Films of tantalum oxide, ranging in thickness from 25 to 2000 nm, were successfully deposited on silicon by the electron cyclotron resonance plasma-enhanced metalorganic chemical vapor deposition (ECR-MOCVD) process at deposition rates of up to 33 nm/min. The films were produced by decomposition of tantalum pentaethoxide into tantalum oxide in an oxygen ECR microwave plasma. The films were amorphous (but fully dense) since the temperature of the substrate, which was unheated, was estimated to be 76–120°C. The growth of the tantalum oxide films was accompanied by the formation of an interlayer of silicon dioxide at the silicon interface. The tantalum oxide films were oxygen rich (relative to Ta₂O₅). The effective relative dielectric constant of these dual-layer dielectrics ranged from ɛ_ef= 8.5 to 24; this range was explained in terms of a bilayer consisting of a 13-nm-thick silicon dioxide layer of ɛ_sx= 4, and a tantalum oxide overgrowth of varying thickness having ɛ_tx∼ 25. A maximum breakdown strength of the films was 6.9 MV/cm and the leakage current at a field of 1 MV/cm was 3.0 × 10^-8. The breakdown properties were related to the presence of stray particles on the substrate; these properties are expected to improve considerably if the processing is carried out in a clean-room environment. The silicon dioxide layer is believed to have grown by the diffusion of oxygen through the tantalum oxide overlayer despite the low substrate temperature.     

Optimization of DC Reactive Magnetron Sputtering Deposition Process for Efficient YSZ Electrolyte Thin Film SOFC

Yttria‐stabilized zirconia (YSZ, ZrO₂:Y₂O₃) thin films were deposited by reactive DC magnetron sputtering with a high deposition rate from a metallic target of Zr/Y in an argon/oxygen atmosphere. Plasma parameters and composition analysis of the gas phase reveal that the sputtering process in the “compound” mode is reached for a 2.5 sccm oxygen flow rate. Deposition onto silicon in “metal” mode at a flow rate close to the transition, allows obtaining at very high deposition rates (>10 μm h^–1) a compact columnar stoichiometric crystallized YSZ film. When deposited on NiO‐YSZ commercial anode, the obtained coatings show the same properties. In spite of the complexity of the substrate (roughness and porosity), a compact and conformed layer was formed. Annealing treatments in air or hydrogen do not significantly alter the structure of the layers. Electrochemical test at 850 °C with a screen‐printed LSM (LaSrMnO₃) cathode exhibits a satisfying gastightness (OCV = 900 mV) and a maximum power density of 350 mW cm^–2.     

等离子体增强化学气相沉积法制备氢化硅膜的自晶化倾向性

为了探寻生长过程中硅膜的自晶化沉积,采用等离子体增强化学气相沉积(PECVD)法沉积了氢化硅薄膜,系统研究了不同沉积阶段所得硅膜微观结构的迁变规律。结果表明,硅膜的显微结构依赖于沉积时间,当沉积时间仅为30min时,所得硅膜的结构为非晶;而当沉积时间延至60min时,硅膜形成微晶颗粒;此后随着沉积时间的增加,晶化程度提高,且非晶区域面积相应减小。另外,硅膜的沉积速率也随沉积时间的增加而增加。在硅膜沉积过程中,随时间不断变化的界面状态可能为其自晶化的主要原因。     

Low Temperature Deposition of High Performance Lead Strontium Titanate Thin Films by in situ RF Magnetron Sputtering

Highly (100) oriented lead strontium titanate (Pb_0.4Sr_0.6TiO₃) thin films were deposited on LaNiO₃ ‐coated Si substrate via radio‐frequency magnetron sputtering method with substrate temperature ranging from 300 to 500°C. The PST thin films were crystallized at a temperature as low as 300°C, which may result from the well‐controlled stoichiometry and the in situ crystallization on seed layer. At an electric field of 400 kV/cm, high tunability of 43% and 57% can be achieved for PST films deposited at 300°C and 500°C, respectively. Moreover, the dielectric response shows weak frequency dependence and the loss factor stays relatively low. The results suggest that such films should be promising candidate for the microwave tunable devices compatible with the current Si technology.     

TiO2薄膜的低温制备以及工艺优化和性能研究

采用改进溶胶-凝胶法,通过浸渍-提拉工艺在载玻片表面低温制备了锐钛型纳米TiO2薄膜,探讨了水量、pH、水浴时间等工艺参数对TiO2的晶型及光催化活性的影响.利用XRD、FT - IR、SEM和UV - Vis光谱等手段对薄膜的物相、结构、表面形貌以及光吸收特性进行了表征,并利用紫外光激发下降解亚甲基蓝溶液来评价TiO2薄膜的光催化活性.结果表明:在低温条件下,所得TiO2薄膜表面均匀平整;随着水量的增加和pH的降低,TiO2晶化程度逐渐提高;水浴前后所制备的TiO2薄膜对紫外光都表现出了极强的吸收特性;水浴处理有利于提高纳米TiO2薄膜的催化活性,80 ℃水浴8h后TiO2薄膜对亚甲基蓝溶液的降解率从20.9％提高到72.1％.