铜层厚度及退火温度对ZnS/Cu/ZnS复合薄膜显微结构与性能的影响

采用磁控溅射技术制备了不同铜层厚度的ZnS/Cu/ZnS复合薄膜,并在不同温度(100~300℃)下对其进行退火处理,研究了铜层厚度和退火温度对复合薄膜物相、表面形貌、透光率和表面电阻等的影响。结果表明:随着铜层厚度增加,复合薄膜的表面粗糙度逐渐减小后趋于平缓,方块电阻逐渐下降;当铜层厚度为16nm时,复合薄膜的最高透光率最大为87%,方块电阻为62.5Ω;随着退火温度升高,复合薄膜中ZnS层结晶性增强,表面出现颗粒团簇;在100℃退火后,铜层厚度为16nm的复合薄膜的最高透光率为89%,方块电阻为46.3Ω。     

非晶SiO_xN_y薄膜的发光特性研究

采用双离子束溅射沉积法制备SiOxNy复合非晶薄膜,傅里叶变换红外光谱(FTIR)及X射线衍射谱(XPS)测试表明,薄膜成分由Si、O、N元素组成,在室温下可观察到样品有波长为400nm(紫光)、470nm(蓝光)的光致发光。根据测试结果分析研究SiOxNy薄膜的可能发光机理:波长为470nm处发光峰来自于硅基薄膜中中性氧空位缺陷(O2≡Si-Si≡O2),是由于氧原子配位的二价硅的单态-单态之间的跃迁所致,其发光强度随退火温度的升高而变化,800℃时最大,高于800℃时慢慢减弱;波长为400nm发光峰的发射与薄膜中的Si、O、N元素所形成的结构有关,它可能来自于Si、O、N元素结构所形成的发光中心,该峰位的强度随退火温度的升高而增强。     

铁铝阻抗匹配靶的精密扩散连接

为了获得某些材料在在高压条件下的物态方程,制备了用于激光驱动状态方程实验的铁铝阻抗匹配靶,研究了铁铝薄膜的精密热扩散连接技术。以冷轧铁薄膜和超精密加工铝薄膜为原料,研究了热复合工艺条件对其表面形貌、结晶性能、连接界面等参数的影响。利用白光干涉共焦显微镜、X射线衍射仪、膜厚测量仪、扫描电镜等仪器对靶件的表面形貌、厚度、结晶特性、残余应力及界面成分分布等进行分析表征,掌握了相关参数的变化趋势。据此优化工艺参数,制备了高质量的铁-铝阻抗匹配靶。对成靶的测试结果显示,其表面粗糙度小于100nm、厚度一致性控制在100nm以内、界面扩散层厚度约为200nm,且未观测到显微缺陷,满足物理实验的具体要求。     

柔性衬底直流磁控溅射ZnO基高性能透明导电薄膜的制备及性能研究

采用直流磁控溅射法,以柔性PET(聚对苯二甲酸乙二醇酯)为基底,通过参数优化以求在室温下制备高性能ZnO/Ag/ZnO多层薄膜。实验中,使用X射线衍射仪(XRD)、原子力显微镜(AFM)、紫外-可见分光光度计、四探针电阻测试仪等仪器分别对ZnO/Ag/ZnO多层薄膜的微观结构、表面形貌、透过率及方块电阻进行测试及表征。结果表明,随着Ag层厚度增加,薄膜方块电阻急剧下降,通过改变ZnO层厚度,可有效调节薄膜光学性能,随着ZnO层厚度增加,可见光区平均透过率先增大后减小。引入品质因子FTC作为评价指标可知,当依次沉积ZnO、Ag、ZnO厚度为50nm、8nm、50nm时,薄膜光电性能最佳,其在可见光平均透过率为82.3%、方块电阻为2.8Ω/、禁带宽度为3.332eV。     

冷轧钢基复合材料复合工艺及复合机理的实验研究

对冷轧钢基复合材料的生产工艺过程进行了实验研究,并根据实验结果探讨了复合机理.实验结果表明,基材钢必须进行表面的毛化处理,表面粗糙度约为Rz=81～101 μm;钢-铝无张力复合轧制所需的总相对压下量ε0为40%≤ε0≤60%,钢-铜无张力复合轧制所需的总相对压下量ε0为ε0≥70%;钢-铝复合后退火温度在320℃左右时,保温时间应在1小时左右;钢-铜复合后退火温度在550°～600℃之间时,适宜的保温时间约为1.5小时.轧制产生机械嵌合,热处理消除内应力、形成一定厚度的合金层,从而使基材与复合材有机成为一体.     

CVD-Si3N4薄膜工艺及性能研究

以三氯硅烷和氨气作为硅源和氮源，利用低压化学气相沉积工艺（LPCVD）在烧结氮化硅表面制备氮化硅薄膜。考察了工艺参数对沉积速率的影响，并对薄膜的组成、结构及硬度等性能进行了分析。结果表明，当载气为N2或N2＋H2、沉积温度为800℃、NH3／HSiCl3流量比为4时是较佳的工艺条件，此时薄膜沉积速率可达23．4nm／min，其膜层主要由Si-N组成，并含有部分Si-O，硬度为HV2865。     

磁控溅射Ni56Mn27Ga17合金薄膜的光学反射特性研究

Ni-Mn-Ga磁性形状记忆合金薄膜是非常有用的多功能材料,为考察其光学反射特性,采用磁控溅射技术在单晶硅衬底上沉积了Ni56Mn27Ga17合金薄膜,并对其表面形貌和光学反射特性进行研究。研究结果表明,薄膜的表面粗糙度随退火温度的升高而增大;在300～800nm波长范围内,薄膜反射率均随波长的减小而降低,且薄膜整体谱线范围内的反射率随退火温度的升高而降低。     

氩气与氮气流量比对磁控溅射法制备TiN薄膜的影响

用直流反应磁控溅射法在Si(100)基底上制备了TiN薄膜,采用X射线衍射仪和原子力显微镜对其结构和形貌进行了表征,利用四探针测试仪测量了TiN薄膜的方块电阻,使用紫外可见分光光度计测定了薄膜反射率;研究了溅射沉积过程中氩气与氮气流量比对TiN薄膜结构及性能的影响.结果表明:在不同氩气与氮气流量比下,所制备薄膜的主要组成相是(200)择优取向的立方相TiN;随着氩气与氮气流量比的增加,薄膜厚度逐渐增大,而表面粗糙度与电阻率先减小后增大;当氩气与氮气流量比为15:1时,薄膜表面粗糙度和电阻率均达到最小值;TiN薄膜的反射率与氩气与氮气流量比的关系不大.     

磁头/磁盘表面保护膜及抗吸附分子膜研究

在中国国家自然科学基金重大项目《先进电子制造中的重要科学技术问题研究》资助下，针对2nm厚度的DLC薄膜的制备和磁头、磁盘间的吸附等问题，探索“磁头、磁盘表面润滑规律和超薄保护膜的生长机理及技术”，目标是寻找磁头、磁盘表面超薄DLC薄膜新的制备方法和制备工艺，发现超薄DLC保护膜的生长机理和生长极限，开发磁头表面抗吸附分子膜的制备技术。报告研究所取得的体系化理论成果。 为了制备厚度为2nm的超薄DLC薄膜，使用FCVA技术代替磁控溅射和CVD技术。通过优化制备参数，制备出厚度为2nm，表面粗糙度为0.128nm，并且连续均匀的DLC薄膜。探索基体形貌对薄膜生长模式的影响规律。发现在脉冲偏压幅值-100V、占空比20%条件下制备的薄膜性能最优     

退火温度对NiTi/Si膜结晶特性及力学性能的影响

采用射频磁控溅射法在NiTi膜表面沉积一层非晶硅膜而形成NiTi/Si膜,并对该膜进行了不同温度的退火处理;用XRD、SEM和纳米压痕仪研究了退火温度对NiTi/Si膜的结晶特性和力学性能的影响。结果表明:NiTi/Si膜在600℃下退火后其中的硅仍为非晶态;当退火温度在650℃后开始出现明显的结晶硅衍射峰,且随着温度升高,硅的结晶度增大,晶粒逐渐长大;而该膜的硬度和抗压痕蠕变能力逐渐降低;该膜弹性模量在650℃退火后最大。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.