近红外区高透射率In2O3:W透明导电氧化物薄膜的研究

采用反应直流磁控溅射法制备了掺钨氧化铟(In2O3W,IWO)透明导电氧化物薄膜.薄膜中掺杂的钨离子与被替代的铟离子之间存在高价态差.与相同电阻率的ITO(In2O3Sn)相比,IWO薄膜具有载流子浓度低、迁移率高和近红外区透射率高的特点.研究了氧分压、溅射电流等参数对IWO薄膜电学和光学性能的影响.制备的多晶IWO薄膜最佳电阻率为3.1×10-4 Ω·cm,最高载流子迁移率为58 cm2 V-1s-1,可见光范围平均透射率大于90%,近红外区(700～2500 nm)平均透射率约为85%.     

In_2O_3：W薄膜的制备及光电性能研究

采用直流磁控溅射法制备了掺钨氧化铟（In2O3：W,IWO）薄膜,研究了制备工艺对薄膜表面形貌和光电性能的影响。结果表明薄膜的表面形貌与其光电性能有着紧密联系。氧分压显著影响薄膜的表面形貌进而对薄膜的光电性能产生影响,同时溅射时间的变化也显著影响薄膜的光电性能：随着氧分压以及溅射时间的升高,薄膜的电阻率均呈现先减小后增大的变化规律,在氧分压为2.4×10-1Pa条件下,制备样品的表面晶粒排布最细密,其电阻率达到6.3×10-4Ω.cm,载流子浓度为2.9×1020cm-3,载流子迁移率为34cm2/（V.s）,可见光平均透射率约为85%,近红外光平均透射率〉80%。     

高迁移率IWO透明导电氧化物薄膜制备及其退火处理研究

采用直流磁控溅射法在清洁玻璃基片上制备了掺钨氧化铟(IWO)透明导电氧化物薄膜.研究了氧分压及其退火处理对IWO薄膜光电性能的影响.实验发现薄膜的光电性能对氧分压非常敏感,退火郸理有助于改善IWO薄膜的电阻率.获得了最小电阻率为2.2×10-4Ω·cm,载流子迁移率为63.5 cm2/V·s,可见光范围平均透射率(含基片)为83.2%的IWO薄膜样品.     

高迁移率透明导电In2O3:Mo薄膜

用直流磁控溅射法成功制备了高价态差掺钼氧化铟(IMO)透明导电薄膜.研究了氧分压,基板温度以及溅射电流对IMO薄膜结构和性能的影响.获得的IMO薄膜的最低电阻率为3.65×10-4 Ω·cm,载流子迁移率高达50 cm2V-1s-1,可见光区域的平均透射率(含玻璃基底)高于80%.X-ray衍射(XRD)研究表明IMO薄膜具有良好的结晶性.分析认为IMO薄膜的载流子迁移率主要受晶界散射的控制.     

掺钼氧化锌透明导电薄膜光学性质研究

采用直流磁控反应溅射制备了掺钼氧化锌透明导电薄膜。研究了掺钼氧化锌薄膜的结构、表面形貌及其光学和电学性能。原子力显微镜扫描显示薄膜表面较为平整致密。制备出的掺钼氧化锌薄膜最低电阻率为9.4×10-4Ω.cm,相应载流子迁移率为27.3cm2V-1s-1,载流子浓度为3.1×1020cm-3。在可见光区域的平均透射率大于85%,折射率(550nm)为1.853,消光系数为7.0×10-3。通过调节氧分压可以调节薄膜载流子浓度,禁带宽度随载流子浓度的增加由3.37增大到3.8eV,薄膜的载流子有效质量m*为0.33倍的电子质量。     

新型透明导电ZnO:Mo薄膜

采用直流磁控反应溅射技术成功制备了新型ZnOMo(ZMO)透明导电薄膜.研究了钼掺杂量和基片温度等参数对ZMO薄膜结构和光电性能的影响.结果表明,薄膜的结构和光电性能与钼含量以及基片温度有关.x光衍射图谱(XRD)显示薄膜具有六角纤锌矿结构,并且在基片温度为200℃,钼含量(Mo/Zn Mo)为1.5wt%时薄膜具有较好的c轴取向.制备出的ZMO薄膜最低电阻率为1.97×10-3 Ω·cm,相应载流子迁移率达37.0 cm2V-1s-1,载流子浓度为8.57×1019 cm-3,在可见光区域的平均透射率达到80%左右.     

衬底温度和氢气退火对ZnO:Al薄膜性能的影响

采用射频磁控溅射法在石英玻璃衬底上制备了性能良好的透明导电ZnO:Al薄膜,并研究了衬底温度和氢气退火对薄膜结构和光电性能的影响。结果表明,衬底加热可以改善薄膜结晶质量和c轴择优取向,减小内应力,并提高其电学性能。经稀释氢气退火后,500℃沉积的薄膜电阻率由9.4×10-4Ω.cm减小到5.1×10-4Ω.cm,迁移率由16.4cm2.V-1.s-1增大到23.3 cm2.V-1.s-1,载流子浓度由4.1×1020cm-3提高到5.2×1020cm-3,薄膜的可见光区平均透射率仍达85%以上。禁带宽度随着衬底温度的升高和氢气退火而展宽。     

室温直流反应磁控溅射制备透明导电In2O3:Mo薄膜

在室温条件下采用直流反应磁控溅射法制备了新型透明导电In2O3:Mo薄膜.研究了溅射压强中氧气百分含量[P(O2)]为8.0%～18.0%时对薄膜光电特性以及表面形貌结构的影响.结果表明,薄膜的光电性能对溅射压强中P(O2)非常敏感.分析显示P(O2)决定了薄膜中的氧空位含量和载流子浓度,从而影响了薄膜的光电特性.原子力显微镜观察表明,适量的P(O2)条件下可以获得平均粗糙度为0.3 nm、颗粒均匀、表面平整的薄膜.室温制备的IMO薄膜在可见光区域的平均透射率(含玻璃基底)高达82.1%,电阻率低至5.9×10-4 Ω·cm.     

P型掺锌硫化铜铝透明导电薄膜的制备和性能研究

采用渠道火花烧蚀技术,在普通玻璃基板上制备掺锌硫化铜铝CuAl0.90Zn0.10S2透明导电薄膜.运用X射线衍射法(XRD)和原子力显微镜(AFM)分析薄膜的晶体结构和表面形貌.研究不同的制备条件对薄膜光电性能的影响.结果显示,薄膜表面平整致密,均为p型导电.氩气压强和基板温度对薄膜的电阻率和载流子浓度具有显著影响,例如,随着氩气压强增加,电阻率会先降低再上升,而载流子浓度则先增加再降低.在优化的制备条件下,薄膜的电阻率最小值为0.2 Ω·cm,载流子浓度为6.67×1018 cm-3,载流子迁移率最大为1.06 cm2V-1S-1.在基板温度Ts=500 ℃时,获得了室温下最高电导率为50.9 S·cm-1的薄膜.薄膜可见光区域的平均透射率大于60%.     

Ar流量对磁控溅射制备Al掺杂ZnO薄膜的影响

Al掺杂ZnO(AZO)具有电导率高、光学透射率高的优点,且原料来源丰富、制备成本低廉,被认为是最有应用潜力的透明导电薄膜。本文利用射频磁控溅射制备30 cm×30 cm尺寸大面积AZO薄膜,研究了气压恒定时,Ar流量对薄膜晶粒生长机制、电学和光学性能的影响。结果表明,AZO薄膜晶粒均表现出垂直基片方向的c轴择优取向生长,随Ar流量增大取向变弱;薄膜表面晶粒尺寸大小分布不均匀,随Ar流量增大,大晶粒数量增多,表面出现长度为100 nm、宽度为30 nm的棒状晶;随着Ar流量增大,载流子浓度由4.52×1020 cm-3略微增大至6.2×1020 cm-3,霍尔迁移率由4.79 cm2(/V·s)提升至10.46 cm2(/V·s),电阻率在Ar流量94 mL/min时达到最低值1.01×10-3Ω·cm。薄膜可见光平均透射率均大于78%,禁带宽度约3.8 eV。     

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.     

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.     

空压机轴承箱蜗壳温度探头油封改造

由于空压机进气侧轴承箱蜗壳温度探头密封效果不好,使空压机及其后续管道受到油污染。后将温度探头的O形圈密封改为骨架油封,杜绝了轴承箱漏油问题。文章简介空压机的结构和技术参数,详细介绍了骨架油封的制作和优点。     

Characteristics of mechanical properties of materials in studies of conditions of attainment of marginal states

It is shown that conditions of attainment of marginal states in the material of structural components are formulated on the basis of analysis of force and deformation criteria of formation and development of destruction. The parameters of these criteria are data on types of structural materials, standard and special characteristics of their mechanical properties, structural forms of considered elements of the equipment, and their operating stress loading. In this case, the construction of a system of state equations for describing interrelation of current damage, external actions, and responses to them is based on the concept of calculating variations in properties of materials at all stages of the design life cycle.     

Determination of parameters of microstructural inhomogeneity of deformation of metals by the method of modeling

The article suggests a method of evaluating the microstructural inhomogeneity of deformation of metals by modeling. The method includes the measurement of deformations of metal according to meshes of a dividing grid with small base and the calculation of the distribution parameters of microdeformations in model representation. It is shown that the modeling method makes it possible objectively to evaluate the microinhomogeneity of deformation of metals independently of the chosen mesh size of the dividing grid. New structural characteristics are introduced: the base and wave of variation expressing the degree of crumbling or amalgamation of metal grains by inhomogeneity of deformation.Translated from Problemy Prochnosti, No. 7, pp. 40–44, July, 1991.     

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.