CVD法制备Sb掺杂SnO2薄膜的结构与性能研究

采用化学气相沉积法（CVD）制备了Sb掺杂SnO2薄膜（ATO），研究了Sb掺杂量对ATO薄膜结构和性能的影响。利用X射线衍射（XRD）、扫描电镜（SEM）、X射线光电子能谱（XPS）等分析手段对所制得薄膜的结构、形貌、成分等进行了表征，XRD结果表明在基板温度为665 ℃时能够制得结晶性能较好的多晶薄膜，XPS分析确定掺杂后的Sb以Sb5+离子形式存在。讨论了Sb掺杂量对方块电阻、透射率和反射率等薄膜性质的影响，结果表明,当Sb掺杂量为2%时取得最小方块电阻为7.8 Ω/□,在可见光区薄膜的透射率和反射率随着Sb掺杂量的增加呈下降趋势。最后探讨了Sb掺杂SnO2薄膜的显色特性，认为Sb5+离子的本征吸收是薄膜显色的主要原因。     

High rate deposition of microcrystalline silicon films by high-pressure radio frequency plasma enhanced chemical vapor deposition (PECVD)

Hydrogenated microcrystalline silicon (μc-Si:H) thin films were prepared by high-pressure radio-frequency (13.56 MHz) plasma enhanced chemical vapor deposition (rf-PECVD) with a screened plasma. The deposition rate and crystallinity varying with the deposition pressure, rf power, hydrogen dilution ratio and electrodes distance were systematically studied. By optimizing the deposition parameters the device quality μc-Si:H films have been achieved with a high deposition rate of 7.8 ?/s at a high pressure. The V _oc of 560 mV and the FF of 0.70 have been achieved for a single-junction μc-Si:H p-i-n solar cell at a deposition rate of 7.8 ?/s. Supported by the National Natural Science Foundation of China (Grant No. 50662003) and the State Development Program for Basic Research of China (Grant No. G2000028208)     

SiC涂层的快速气相沉积

介绍了一种采用化学气相沉积技术，利用SiCl4 CH4体系快速沉积SiC涂层的方法，并讨论了工艺条件对沉积过程的影响．结果表明，采用SiCl4 CH4体系在900℃便可实现SiC的快速沉积，此方法所得SiC涂层的纯度不高，但适用于制备构件的抗烧蚀涂层．     

Fabrication of micro carbon pillar by laser-induced chemical vapor deposition

Argon ion laser was used as the induced light source and ethane(C2H4) was selected as the precursor gas,in the variety ranges of laser power from 0.5 W to 4.5 W and the pressure of the precursor gas from 225×133.3 Pa to 680×133.3 Pa,the experiments of laser induced chemical vapor deposition were proceeded for fabrication of micro carbon pillar.In the experiments,the influences of power of laser and pressure of work gas on the diameter and length of micro carbon pillar were investigated,the variety on averaged growth rate of carbon pillar with the laser irradiation time and moving speed of focus was discussed.Based on experiment data,the micro carbon pillar with an aspect ratio of over 500 was built through the method of moving the focus.     

Thickness and component distributions of yttrium-titanium alloy films in electronbeam physical vapor deposition

Thickness and component distributions of large-area thin films are an issue of international concern in the field of material processing. The present work employs experiments and direct simulation Monte Carlo (DSMC) method to investigate three-dimensional low-density, non-equilibrium jets of yttrium and titanium vapor atoms in an electron-beams physical vapor deposition (EBPVD) system furnished with two or three electron-beams, and obtains their deposition thickness and component distributions onto 4-inch and 6-inch mono-crystal silicon wafers. The DSMC results are found in excellent agreement with our measurements, such as evaporation rates of yttrium and titanium measured in-situ by quartz crystal resonators, deposited film thickness distribution measured by Rutherford backscattering spectrometer (RBS) and surface profilometer and deposited film molar ratio distribution measured by RBS and inductively coupled plasma atomic emission spectrometer (ICP-AES). This can be taken as an indication that a combination of DSMC method with elaborate measurements may be satisfactory for predicting and designing accurately the transport process of EBPVD at the atomic level. Supported by the National Natural Science Foundation of China (Grant Nos. 90205024, 10502051 and 10621202)     

Synthesis of aligned carbon nanotubes by thermal chemical vapor deposition

Single crystal silicon was found to be very beneficial to the growth of aligned carbon nanotubes by chemical vapor deposition with C₂H₂ as carbon source. A thin film of Ni served as catalyst was deposited on the Si substrate by the K575X Peltier Cooled High Resolution Sputter Coater before growth. The growth properties of carbon nanotubes were studied as a function of the Ni catalyst layer thickness. The diameter, growth rate and areal density of the carbon nanotubes were controlled by the initial thickness of the catalyst layer. Steric hindrance between nanotubes forces them to grow in well-aligned manner at an initial stage of growth. Transmission electron microscope analysis revealed that nanotubes grew by a tip growth mechanism. Funded by the National Natural Science Foundation of China (No. 50435030)     

Synthesis of carbon nanotubes using Cu-Cr-O as catalyst by chemical vapor deposition

A novel powder catalyst Cu-Cr-O applied to the synthesis of carbon nanotubes(CNTs) was developed, which was prepared via ammonia precipitation method. Techniques of thermo-gravimetric/ differential scanning calorimeter(TG-DSC), X-ray diffraction(XRD) as well as scanning electron microscopy(SEM) and transmission electron microscopy(TEM) have been employed to characterize the thermal decomposition procedure, crystal phase and micro structural morphologies of the as-synthesized materials, respectively. The results show that carbon nanotubes are successfully synthesized using Cu-Cr-O as catalyst when the precursors are calcined at 400, 500, 600, and 700 ℃. The results indicate that the calcination of the Cu-Cr-O catalyst at 600 ℃ is an effective method to get MWCNT with few nano-tube defects or amorphous carbons.     

化学液相沉积法制备AlxOy薄膜

给出了用化学液相沉积法(CLPD)制备A1xOy／Si薄膜的方法，室温下生长2h得到A1xOy／Si薄膜，其退火温度为1000℃，退火时间2h．对薄膜的显微硬度、成分和结构进行了检测和分析．结果表明，薄膜的显微硬度在退火前为5202．0N／mm^2，退火后为14533．5N／mm^2，增加近3倍；高温退火去掉了膜内的0H^-1，同时使薄膜晶化，晶体薄膜的O／A1比例为1．3．     

化学液相沉积法制备Al_xO_y薄膜

给出了用化学液相沉积法(CLPD)制备Al_xO_y/Si薄膜的方法,室温下生长2h得到Al_xO_y/Si薄膜,其退火温度为1000℃,退火时间2h。对薄膜的显微硬度、成分和结构进行了检测和分析。结果表明,薄膜的显微硬度在退火前为5202.0N/mm~2,退火后为14533.5N/mm~2,增加近3倍;高温退火去掉了膜内的OH~(-1),同时使薄膜晶化,晶体薄膜的O/Al比例为1.3。     

Synthesis and oxidation behavior of boron-substituted carbon powders by hot filament chemical vapor deposition

Boron-substituted carbon powder, B _x C_1−x with x up to 0.17, has been successfully synthesized by hot filament chemical vapor deposition. The boron concentration in prepared B _x C_1−x samples can be controlled by varying the relative proportions of methane and diborane. X-ray diffraction, transmission electron microscopy, and electron energy loss spectrum confirm the successful synthesis of an amorphous BC₅ compound, which consists of 10–20 nm particles with disk-like morphology. Thermogravimetry measurement shows that BC₅ compound starts to oxidize approximately at 620°C and has a higher oxidation resistance than carbon. Supported by the National Natural Science Foundation of China (Grant Nos. 10474083, 50472051, 50532020, 50672081) and the National Basic Research Program of China (Grant No. 2005CB724400)     

铝基底上SiOx陶瓷膜层的CVD制备及结构性能

本研究采用常压化学气相沉积(CVD)的方法在金属铝基底上制备出硅氧化合物陶瓷膜层。介绍了陶瓷膜层的制备工艺及设备。通过SEM、TEM观察了该膜层的形貌，并用XPS测定了膜层的成分，用TEM分析了陶瓷膜层的结构特征。通过拉伸实验、划痕实验及弯曲实验考察了陶瓷膜层与铝基底的结合性能，结果表明，膜层与基底的结合非常好。     

Preparation and characteristics of C/C composite brake disc by multi-cylindrical chemical vapor deposition processes

1INTRODUCTION C/Ccompositeisakindofmultifunctioncom posite,whichhasmanyspecialproperties,suchas excellentheat resistantpropertyanddimensional stability,highspecificstrengthandmodulus,as wellaslowthermalexpansioncoefficientandwear rate[15].Itistheonlyheat structuralmaterialthat canworkinnon oxygenandattemperatureover1600℃foralongtime.Moreover,itsspecific thermalcapacityistwiceaslargeasthatofcom monmetalmaterialanditsheat conductivitycanbe designedasrequired.Therefore,C/Ccomposite haswide…     

聚酰亚胺的制备及其性能表征

以均苯四酸二酐(PMDA)为二酐单体,对苯二胺(PDA)为二胺单体,通过低温缩聚合成一系列聚酰胺酸(PAA)和聚酰亚胺(PI)薄膜,对其结构和力学性能进行表征。结果表明,聚酰胺酸的酰亚胺化较完全,PMDA-PDA聚酰亚胺薄膜的拉伸强度达到290 MPa。     

基片温度对金刚石厚膜生长的影响

采用微波等离子体化学气相沉积（MPCVD）法制备了Ф60mm的金刚石厚膜,通过对沉积过程和结果的观察发现,由于所用沉积气压较高,基片不同区域温度不均匀,导致不同区域沉积的金刚石厚膜晶型差距较大．通过对不同区域的结果进行比较,发现850℃为较好的沉积温度,并在对沉积工艺进行优化后,采用该温度在Ф60mm的基片上制备了厚度为0．6mm取向性很好的金刚石厚膜．     

Simple method to rapidly fabricate chain-like carbon nanotube films and its field emission properties

A simple process to fabricate chain-like carbon nanotube (COT) films by microwave plasma-enhanced chemical vapor deposition (MPCVD) was developed successfully. Prior to deposition, the Ti/Al2O3 substrates were ground with Fe-doped SiO2 powder. The nano-structure of the deposited films was analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. The field electron emission characteristics of the chain-like carbon nanotube films were measured under the vacuum of 10-5 Pa. The low turn-on field of 0.80 V/μm and the emission current density of 8.5 mA/cm2 at the electric field of 3.0 Vμ/m are obtained. Based on the above results, chain-like carbon nanotube films probably have important applications in cold cathode materials and electrode materials.     

聚酰亚胺衬底CIGS薄膜附着性的改善

为改善聚酰亚胺(PI)衬底Cu(In,Ga)Se2(CIGS)薄膜的附着性,提出在NaF沉积前预先在Mo层上蒸发沉积100nm厚的In-Ga-Se(IGS)薄膜的新掺Na工艺。结果表明:这种IGS-NaF-CIGS式新工艺可显著改善CIGS薄膜的附着,而且CIGS薄膜材料和器件特性没有显著退化;新工艺促进了NaInSe2的生成,减少了In-Se二元相的残余,但也造成薄膜电阻率的升高和电池填充因子的下降,进而导致制备的PI衬底CIGS电池的转换效率由9.8%降至9.0%。综合考虑附着性的改善和器件效率的轻微下降,新工艺利大于弊,有很好的应用前景。     

Synthesis and characterization of well-aligned carbon nitrogen nanotubes by microwave plasma chemical vapor deposition

Well-aligned carbon nitrogen nanotube films have been synthesized successfully on meso-porous silica substrates by microwave plasma chemical vapor deposition (MWPCVD) method. Studies on their morphology, structure, and composition by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDX), respectively, indicate that these nanotubes consist of linearly polymerized carbon nitrogen nanobells, and the nitrogen atoms have been doped into carbon netweork to form a new structure C1-xNx( x = 0.16±0.01). X-ray photoelectron spectroscopy (XPS) results of the samples further demonstrate that carbon bonds cova-lently with nitrogen in all the carbon nitrogen nanotube films.     

Adhesive strength of CVD diamond thin films quantitatively measured by means of the bulge and blister test

Large advancement has been made in understanding the nucleation and growth of chemical vapor deposition (CVD) diamond, but the adhesion of CVD diamond to substrates is poor and there is no good method for quantitative evaluation of the adhesive strength. The blister test is a potentially powerful tool for characterizing the mechanical properties of diamond films. In this test, pressure was applied on a thin membrane and the out-of-plane deflection of the membrane center was measured. The Young’s modulus, residual stress, and adhesive strength were simultaneously determined using the load-deflection behavior of a membrane. The free-standing window sample of diamond thin films was fabricated by means of photolithography and anisotropic wet etching. The research indicates that the adhesive strength of diamond thin films is 4.28±0.37 J/m2. This method uses a simple apparatus, and the fabrication of samples is very easy.