O2流量对磁控溅射N掺杂TiO2薄膜成分及晶体结构的影响

利用直流脉冲磁控溅射方法在室温下通过改变O₂流量制备具有不同晶体结构的N掺杂TiO₂薄膜,利用台阶仪、X射线光电子能谱仪、X射线衍射仪、紫外-可见分光光度计等设备对薄膜沉积速率、化学成分、晶体结构、禁带宽度等进行分析.结果表明:所制备的薄膜元素配比约为TiO_1.68±0.06N_0.11±0.01,N为替位掺杂,所有样品退火前后均未形成Ti—N相结构,N掺杂TiO₂薄膜的沉积速率、晶体结构等主要依赖于O₂流量.在O₂流量为2 sccm时,N掺杂TiO₂薄膜沉积速率相对较高,薄膜为非晶态结构,但薄膜内含有锐钛矿(anatase)和金红石(rutile)相晶核,退火后薄膜呈anatase和rutile相混合结构,禁带宽度仅为2.86 eV.随着O₂流量的增加,薄膜沉积速率单调下降,退火后样品禁带宽度逐渐增加.当O₂流量为12 sccm时,薄膜为anatase相择优生长,退火后呈anatase相结构,禁带宽度为3.2 eV.综合本实验的分析结果,要在室温条件下制备晶态N掺杂TiO₂薄膜,需在高O₂流量(＞10 sccn)条件下制备. 关键词： 2薄膜')" href="#">N掺杂TiO₂薄膜 磁控溅射 化学配比 晶体结构     

电介质表面纵向射频电场对次级电子倍增效应的影响

基于次级电子倍增动力学模型和次级电子发射曲线,运用蒙特卡罗方法模拟电介质表面具有纵向射频电场作用下的单边次级电子倍增现象,研究次级电子倍增的表面电场敏感曲线和时间演化图像. 以一个S波段射频介质窗为例,计算次级电子在其介质表面的沉积功率. 结果表明,纵向射频电场可能加剧电介质表面的次级电子倍增效应,易于导致介质片破裂,不利于高频能量传输. 关键词： 纵向射频场 次级电子倍增效应 蒙特卡罗方法 功率沉积     

A NEW ROPER-SUFFRIDGE EXTENSION OPERATOR ON BOUNDED COMPLETE REINHARDT DOMAINS

In this paper, we construct a new Roper-Suffridge extension operator Φr n,β1,,βn(f)(z) = F(z) = ((rf(z1/r)/z1)β1z1,(rf(z1/r)/z1)β2z2,...,(rf(z1/r)/z1)βnzn)',where f is a normalized locally biholomorphic function on the unit disc D, r = sup{|z1| : z =(z1, ···, zn) ∈Ω}, β1∈ [0, 1], 0 ≤βk≤β1, k = 2, ···, n, then we prove it can preserve the property of spirallikeness of type β, almost starlikeness of order α and starlikeness of orderα on bounded complete Reinhardt domain Ω, respectively.     

梯度磁场中薄膜厚度梯度的形成机理

借助于基片下方放置的磁铁，在溅射的放电空间中引入了纵向的梯度磁场，辉光放电时，其外貌发生了显著的收缩，由此沉积的薄膜在平面内存在明显的厚度梯度，用磁场中带电粒子的运动理论解释了此种薄膜的形成机制。     

纳米GaSb-SiO2镶嵌复合薄膜的制备及光学性质

用射频磁控溅射技术制备出纳米GaSb颗粒镶嵌在SiO2介质中的复合薄膜.透射电子显微镜观察表明, 纳米GaSb颗粒均匀地镶嵌在SiO2介质中.X射线衍射显示出GaSb (111),GaSb(220) 和GaSb(311)典型的面心立方闪锌矿结构特征.复合薄膜的室温光吸收谱表明,吸收边发生了较大的蓝移,并且,蓝移量随纳米GaSb的颗粒尺寸减小而增大.复合薄膜的室温Raman光谱表明: 薄膜的Raman散射峰较块体材料的有较大的红移和宽化.用量子限域理论和张应力效应对这些现象作了解释.     

Online re-optimization of optical filters on a production sputter tool

This contribution presents a magnetron sputter deposition tool with broadband optical monitor and online re-optimization capability for high volume production. The layer termination relies on a comparison of the actually measured reflection spectrum with a pre-calculated target spectrum. Spectra recorded after each deposited layer are analyzed by the re-optimization module and in case of significant deviations layer thicknesses and target spectra for the remaining layers are recalculated. This technique significantly improves the performance and reproducibility in case of highly denlanding coating designs and is able to correct abnormal production errors in individual layers, which will lead to coating failure without re- optimization.     

ZnO纳米线的制备

利用磁控溅射技术在Si衬底上沉积的锌膜进行热氧化后,得到一维ZnO纳米线。     

雷达前端射频装置效应实验

本报告介绍了雷达前端射频装置的基本组成、特性、工作原理和性能，提出了微波效应实验方法，通过注入法和辐照法的研究，摸索雷达前端射频装置的效应规律和效应阈值。对雷达前端射频装置进行了微波效应实验研究，即采用注入法，将低功率的微波直接注入雷达前端电路和它的单元器件，或采用辐照法近距离辐照雷达前端，模拟微波对它的作用，而摸索雷达前端射频装置的微波效应规律。微波脉冲对射频装置造成损伤，应是在微波脉冲作用下，使射频装置不能完成其正常功能。射频装置的功能受损，体现为系统增益下降。     

Influence of Thickness of Field Emission Characteristics of Nanometre Boron Nitride Thin Films

Nanometre boron nitride (BN) thin films with various thickness (54-135nm) were prepared on Si(100) by rf magnetic sputtering physical vapour deposition. The field emission characteristics of the BN thin films were measured in an ultrahigh vacuum system. A threshold electric field of 11V/μm and the highest emission current density of 240μA/cm^2 at an electric field of 23V/μm were obtained for the about 54-nm-thick BN film. The threshold electric field increases with increasing the thickness in the nanometre range. The Fowler-Nordheim plots show that electrons were emitted from BN to vacuum by tunnelling through the potential barrier at the surface of BN thin films.     

用于放射性束流的RFQ冷却聚束器

简要概述RFQ冷却聚束器的基本原理, 并给出了利用SIMION程序模拟的部分结果. 设计中的RFQ冷却聚束器与国际上其它同类设备相比, 具有特征半径大、入射粒子的允许能量上限值高和氦气气压高的特点, 因此本文最后对需要克服的困难作了一个简要的阐述.