Optimization of process parameters for sputtering of ceramic ZnO:Al2O3 targets for a-Si:H/μc-Si:H solar cells

Aluminum doped ZnO layers with a thickness of 800 nm were deposited dynamically by d.c. magnetron sputtering from a ceramic planar ZnO: Al₂O₃ target (1 wt.%). A wide range of process parameters, namely oxygen partial pressure, total pressure and power, was covered, while temperature was held constant at 300 °C. Visual absorption in the range of 2.3-4.7% and resistivities between 380 and 2150 µΩcm were obtained. In addition static imprints were performed to reveal the dependence of layer properties on target erosion. It was shown, that films deposited from targets with a race track deeper than 1.8 mm had very stable etching morphologies as well as optical and electrical properties in the range of the observed process parameters. In contrast, a new target yields very different etching structures and an increased resistivity.     

多源多目标扫掠体的全六面体网格自动生成算法

为实现多源多目标扫掠体六面体网格生成,提出针对该类形体的全六面体网格自动生成算法.该算法结合虚面和虚拟分解算法,将多源多目标扫掠体自动分解为多个多源扫掠子体;再采用多源扫掠网格生成方法生成各子体网格,整体网格则由各子体网格自动组合而成.文中给出了完整的虚拟分解算法,在虚拟分解流程中的"压印"环节利用改进的边界约束Delaunay三角化方法统一处理各类情形,避免了传统算法复杂的分类讨论.最后给出多个网格实例及其网格质量数据,验证了文中算法的实用性.     

基于小波多尺度分解的印鉴图像配准

论文提出了一种基于小波多尺度分解的印鉴配准方法。用一维环投影向量的循环移位来代替二维图像的旋转。利用小波分解结果,采用大尺度特征向量来进行相关性分析,实现图像配准。其主要优点是算法具有很强的抗干扰性并且具有广泛的适用性。     

纳米焊膏与21世纪电路安装技术

概述了低温烧结型纳米胶的特性和应用纳米胶形成细线化图形的工艺。     

尿嘧啶分子印迹P(AN-co-MAA)共聚物铸膜液动态流变行为

采用动态流变学方法研究了尿嘧啶分子印迹丙烯腈与甲基丙烯酸共聚物(P(AN-co-MAA))铸膜液的流变行为.对于P(AN-co-MAA)共聚物铸膜液体系,其复合黏度η*,在振荡频率≤1.263 Hz时,变化甚微,当振荡频率≥3.47 Hz时,η*大幅度下降;当尿嘧啶含量为1%时,体系的η*最大,并且随振荡频率的增加,下降的幅度增大.在1%～3%的尿嘧啶含量范围内体系的黏度η随尿嘧啶含量的增加而增加,随温度的升高而降低,尿嘧啶含量越大,黏度随温度变化越敏感.     

Anti‐reflection and hydrophobic characteristics of M‐PDMS based moth‐eye nano‐patterns on protection glass of photovoltaic systems

To maximize the incident light, moth‐eye nano‐patterns were formed on a glass plate that was used as the protection glass for photovoltaic systems. These moth‐eye nano‐patterns were formed using a nano‐imprint lithography process and increased the transmittance of the glass plate by minimizing the reflection of light at the surface. After the formation of the moth‐eye nano‐patterns, the surface was coated with a trichloro‐silane based self‐assembled monolayer in order to create a hydrophobic surface because the hydrophobic surface induced a self‐cleaning effect. The transmittance of the glass plate increased from 91 to 94% at wavelength of 500 nm after the moth‐eye structure was introduced. Thus, the short circuit current (J_SC) of the I–V characteristics and the charged capacity of the photovoltaic system increased up to 6% after replacing the conventional protection glass with the moth‐eye nano‐patterned glass. The durability of the moth‐eye nano‐patterns was evaluated with respect to an acidic environment, high temperatures and UV irradiation. From these evaluation results, the values of the transmittance and contact angle did not decrease after the nano‐patterns were soaked in sulfuric acid solutions with a pH of 2.0 for 48 h, exposed to a temperature of 120°C for 48 h, and irradiated 10 times with UV light for 4 h. Copyright © 2010 John Wiley & Sons, Ltd.     

Ferroelectric Self‐Poling,Switching, and Monoclinic Domain Configuration in BiFeO3 Thin Films

Self‐poling of ferroelectric films, i.e., a preferred, uniform direction of the ferroelectric polarization in as‐grown samples is often observed yet poorly understood despite its importance for device applications. The multiferroic perovskite BiFeO₃, which crystallizes in two distinct structural polymorphs depending on applied epitaxial strain, is well known to exhibit self‐poling. This study investigates the effect of self‐poling on the monoclinic domain configuration and the switching properties of the two polymorphs of BiFeO₃ (R′ and T′) in thin films grown on LaAlO₃ substrates with slightly different La_0.3Sr_0.7MnO₃ buffer layers. This study shows that the polarization state formed during the growth acts as “imprint” on the polarization and that switching the polarization away from this self‐poled direction can only be done at the expense of the sample's monoclinic domain configuration. The observed reduction of the monoclinic domain size is largely reversible; hence, the domain size is restored when the polarization is switched back to its original orientation. This is a direct consequence of the growth taking place in the polar phase (below T_c). Switching the polarization away from the preferred configuration, in which defects and domain patterns synergistically minimize the system's energy, leads to a domain state with smaller (and more highly strained and distorted) monoclinic domains.     

基于环投影模板匹配的印鉴鉴别法

本文分析了几种印鉴鉴别方法的优缺点,并提出了一种基于环投影模板匹配的印鉴鉴别方法。该方法先将印鉴图像分成若干个区域环,提取反映印鉴本质特征的参数形成局部和全局特征。然后利用一维模板匹配法分别对印鉴边框和印鉴边框内部字信息进行鉴别。实验结果证明,该鉴别方法具有较强的适应性和可靠性。     

紫外压印模版的制备

概述了紫外压印的原理及其优点,并通过对紫外压印模版特殊性的分析,提出了两种紫外压印模版的制作。用反应离子刻蚀法制作了玻璃模版,用浇灌法制作了聚二甲基硅氧烷(PDMS)模版,最后给出了实验过程和结果。实验表明,用反应离子刻蚀法可以制作出具有100 nm特征尺寸、图形的深度为50 nm的玻璃模版,而且通过控制刻蚀时间可以得到需要的图形深度。用浇灌法可以制作出具有100 nm特征尺寸、图形深度为145 nm的聚合物模版。