SiO2/Si上直流磁控反应溅射制备AIN薄膜

利用正交设计分析了直流磁控溅射中溅射气压,衬底温度和N2浓度对SiO2/Si衬底上制备的AIN薄膜的（002）择优取向的影响水平。利用X-射线衍射（XRD）、场发射扫描电镜（FESEM）、原子力显微镜（AFM）对薄膜的晶向和表面形貌进行了分析,得到制备高度择优取向的AIN薄膜的最佳期望条件：衬底温度为250℃,溅射气压为2Pa,N2浓度为75％;并得出了氮气浓度对薄膜的（002）择优取向的影响较大。具有择优取向的AIN薄膜的折射率约为2．06。     

中频反应磁控溅射制备AlN薄膜的工艺研究

利用中频反应磁控溅射成功制备了AIN薄膜。研究了过程参数例如靶电流、溅射气压和氮浓度对AIN薄膜沉积速率和光学性能的影响规律。实验结果表明，在优化制备工艺的基础上，能够制备出具有优良光学性能（高折射率、低消光系数、高透射率）的AIN薄膜。     

潘宁放电溅射沉积纳米级AlN薄膜的性质

设计并制造了新的潘宁型等离子体源实验装置，分析了等离子体的发射光谱和产生AIN的动力学机理。在室温条件下，纯氮气的工作环境中用潘宁放电离子源溅射的方法，在Si（100）衬底上制备了纳米级的光滑平整AIN薄膜。本文用扫描电镜（SEM），原子力显微镜（ATM），红外吸收光谱（FTIR）和拉曼光谱（Raman shift）等测试分析技术用来研究了薄膜的微结构特征。     

Bi4Ti3O12层状铁电薄膜的结构与性能研究

采用脉冲激光沉积法(pulsed laser deposition,PLD),通过改变气氛氧压、衬底温度等工艺参数,在商业化的Pt/TiO2/SiO2/Si衬底上制备了Bi4Ti3O12(BIT)系列薄膜.利用X射线衍射(XRD)表征了薄膜的结构特征;并采用RT2000进行铁电性能参数的测量,以此研究了工艺参数对薄膜结构和铁电性能的影响规律.分析结果表明,调整工艺参数能有效改善BIT薄膜的a轴取向度:气氛氧压越大、衬底温度越高,则薄膜的a轴取向度越高,剩余极化值也就越大.通过上述试验结果得到,在Pt/TiO2/SiO2/Si衬底上制备BIT薄膜的优化条件为氧分压35Pa、衬底温度700℃.在此优化条件下制备的BIT薄膜为a轴择优取向,剩余极化值达到7μC/cm2.     

电流密度和衬底处理方式对CaMoO4薄膜电化学制备的影响

主要研究了利用恒电流电化学技术制备CaMoO4薄膜的工艺中,电流密度和衬底处理方式对薄膜制备的影响.研究发现,增大阳极氧化电流密度会加快薄膜的生长速度,但会加剧晶粒团簇生长的趋势、减弱薄膜与衬底的附着力和薄膜的均匀性;衬底的不同处理方式对薄膜晶粒的生长速度、沉积方式、均匀性等有较大的影响,在抛光衬底上薄膜的沉积速度比酸腐蚀和粗磨的衬底要快,且不易造成晶粒的团簇生长.结果表明,CaMoO4薄膜的电化学沉积,应在抛光衬底上进行;电流密度控制在0.5mA/cm2附近比较好.     

SrTiO3衬底上溅射法外延生长PLZT薄膜

用射频磁控溅射法在SrTiO3衬底上外延生长PLZT薄膜,研究了不同的溅射工艺对薄膜生长速率的影响,探讨了不同的后期热处理条件与薄膜取向度的关系.在SrTiO3衬底上成功制备出外延生长的、厚度达1.5μm的PLZT薄膜.     

RF溅射钕掺杂ZnO薄膜工艺与结构研究

通过射频磁控溅射技术在Si(111)衬底上制备了未掺杂和Nd掺杂ZnO薄膜,研究了衬底温度、氧分压以及Nd不同掺杂浓度等工艺参数对薄膜的影响.薄膜的结构和表面形貌通过XRD分析和AFM观测,表明制备的薄膜为ZnO:Nd纳米多晶薄膜,其表面形貌粗糙,不同沉积条件对薄膜生长有很大的影响.在纯氩气氛中、衬底温度为300℃的条件下,ZnO:Nd薄膜具有c轴择优取向.     

用平面磁控溅射低温生长C轴择优取向的AIN薄膜

本文介绍了用 x-射线衍射仪、扫描电镜和透射电镜来分析用直流平面磁控溅射法在载波片上生长的 AIN 薄膜的结构,结果表明 AIN 薄膜的(002)晶面与基片表面平行,迴摆曲线分析得出标准偏差σ≈0.7°,俄歇谱分析结果表明制得的 AIN 薄膜是高纯的。这种方法适于制取 C轴高度择优取向 AIN 薄膜。     

VO2镀膜工艺与薄膜导电特性的研究

利用射频磁控溅射方法制备了VO2薄膜,通过正交试验设计研究镀膜工艺因素对薄膜导电特性的影响规律.试验结果表明,影响薄膜导电性能的主要因素是热处理温度,其次是衬底的温度,溅射功率和工作压强对薄膜导电性能的影响很小.X射线衍射结果表明,制备的VO2薄膜为非晶体结构,480℃真空热处理后,VO2薄膜结晶良好.由此得到制备VO2薄膜的最优化工艺为:衬底的温度400℃、热处理温度480℃、溅射频率120W和工作气压1.5Pa.     

AIN电子薄膜材料的研究进展

AIN是一种在热、电、光和机械等方面具有良好综合性能的材料，作为电子薄膜材料在微电子、电子元件、高频宽带通信以及功率半导体器件等领域有广泛应用。简介了AIN薄膜的制备方法，评述了国内外各科研团体的最新研究成果和进展，阐述了AIN薄膜的应用，并综述了近年来AIN薄膜作为缓冲层、SOI结构的绝缘埋层和吉赫兹级声表面波器件压电薄膜的研究现状。     

Estimation of Parameters of Universal Distribution of Moments of Failure of Products

A method is proposed for estimating the parameters of a mixture of exponential and Weibull distributions for which the accuracy of preliminary estimates obtained by graphical analysis is refined in accordance with the criterion of maximum likelihood. The efficiency of the proposed method is supported by the results of statistical modeling.     

Evaluation of optical properties of highly scattering media by moments of distributions of times of flight of photons

A novel method for the determination of the optical properties of tissue from time-domain measurements is presented. The data analysis is based on the evaluation of the first moment and the second centralized moment, i.e., the mean time of flight and the variance of the measured distribution of times of flight (DTOF) of photons injected by short (picosecond) laser pulses. Analytical expressions are derived for calculation of absorption and of reduced scattering coefficients from these moments by application of diffusion theory for infinite and semi-infinite homogeneous media. The proposed method was tested on experimental data obtained with phantoms, and results for absorption and reduced scattering coefficients obtained by the proposed method are compared with those obtained by fitting of the same data with analytical solutions of the diffusion equation. Furthermore, the accuracy of the moment analysis was investigated for a range of integration limits of the DTOF. The moment analysis may serve as a comparatively fast method for evaluating optical properties with sufficient accuracy and can be used, e.g., for on-line monitoring of optical properties of biological tissue.     

Assessment of intakes of mixtures of radionuclides

Australia has several uranium mines and a large number of mineral sand mines, with associated processing facilities. Exposures resulting from these mining and processing operations usually involve intakes of mixtures of radionuclides. This work describes the development of a suite of first order, linear compartment models, based on the ICRP Publication 66 respiratory tract model, and an analytical solution to the decay equations, for assessing the consequences of such intakes. The computer programs based on these models directly compute excretion, organ retention and organ and whole-body doses for intakes of either single radionuclides or any mixture of radionuclides belonging to the same radioactive decay chain. The intake can be via inhalation, ingestion or injection, and can be acute, chronic or of limited duration. The starting concentration and degree of secular (dis)equilibrium can be specified for each radionuclide. No assumptions need to be made about the relative magnitudes of the radioactive half-lives of the different nuclides.     

Estimation of potentialities of methods of summation of direct measurement errors

Conventional methods for summation of direct measurement errors are considered. Conditions under which these methods provide consistent results are stated. It is proposed to utilize for characteristic of the total error, its interval estimator or the half-sum of the value obtained by adding up its arithmetic and geometric random errors.Translated from Izmeritel'naya Tekhnika, No. 4, pp. 10–12, April, 1995.     

卧式金属罐容量的测量结果不确定度

本文根据多年的实践检定经验 ,参照JJF1 0 59- 1 999《测量不确定度评定与表示》以及《测量不确定度表达 1 0讲》 ,对卧式金属罐容量的测量结果不确定度进行了评定。     

盐酸浓度不确定度的评估

通过对盐酸浓度标定的过程分析，找出影响结果的各个分量，进行不确定度的评定，按照计量技术规范给出标准的表示法。     

Analysis of the rate of propagation of the wave of change of boiling modes

An approximate analytical expression is derived for the velocity of the front of the wave of change of boiling modes on a rod and on a plate. The impact of the Thomson effect and of the heater orientation in the gravity field is included. Adequate agreement is demonstrated between the derived relations and experimental data.