Mo/Si软X射线多层膜的界面粗糙度研究

 用磁控溅射法分别制备了以Mo膜层和Si膜层为顶层的Mo/Si多层膜系列, 利用小角X射线衍射确定了各多层膜的周期厚度。以不同周期数的Mo/Si多层膜的新鲜表面近似等同于同一多层膜的内界面,通过原子力显微镜研究了多层膜界面粗糙度随膜层数的变化规律。并在国家同步辐射实验室测量了各多层膜的软X射线反射率。研究表明：随着膜层数的增加,Mo膜层和Si膜层的界面粗糙度先减小后增加然后再减小,多层膜的峰值反射率先增加后减小。     

金刚石膜/硅基体热残余应力场有限元分析

运用ANSYS软件建立了有限元模型,对化学气相沉积在硅基体上的金刚石膜内部和膜/基交界面处的各热残余应力分量的分布作了计算与分析.所建模型与已有的一维解析模型都能得出厚度截面上的法向应力分量的分布,且吻合较好,而前者的优点在于它还能模拟切向应力和剪应力等其它应力分量,这对分析膜/基界面的粘附与失效是至关重要的.     

Si_2P_2分子结构和光谱的理论研究

用密度泛函方法 [B3LYP/6- 31 1G(d) ]研究了Si2 P2 分子的各种可能异构体的结构、能量和红外光谱 .结果表明 :Si2 P2 分子有 5个稳定的异构体 ,能量最低的异构体为具有P—P桥键的蝴蝶形结构 ,其次为具有Si—Si桥键的菱形结构 ,而具有Si—Si中心键的直线结构能量最高 .并进一步将Si2 P2 和C2 N2分子在结构和能量上的差异进行了比较和分析 .     

烷基苯基五元杂环基锡化合物的^13C—NMR研究

本文测定了18个含有各种烷基、苯基、烯丙基、五元杂环及其它极性基团的有机锡化合物的~(13)C—NMR谱。对全部谱线进行了归属。讨论了烷基锡、苯基锡中Sn—C键的性质和极性取代基对C—1δ值的影响。考察了各类C-Sn偶合常数大小顺序,以及~1J_(C-)~(119)Sn与~1J_(C-)~(117)Sn的关系。     

微透镜制作中光刻胶与衬底匹配行为的研究

利用光刻/离子束刻蚀制作大面阵硅微透镜阵列,采用SEM和表面探针测试等手段分析所制样品的形貌特点,定性讨论制备工艺的不同对所制器件的影响.所用工艺为大面阵微尖阵列和微合阵列的离子束刻蚀制作奠定了基础.     

Partial averaging for impulsive differential equations with supremum

Partial averaging for impulsive differential equations with supremum is justified. The proposed averaging schemes allow one to simplify considerably the equations considered.     

Real time observation of oxygen chemisorption states on Si(0 0 1)-2×1 during supersonic oxygen molecular beam irradiation

Employing Si 2p and O 1s photoemission spectroscopy using monochromated synchrotron radiation and the supersonic molecular beam technique, we have performed real time in situ observations of oxidation states on Si(0 0 1)-2×1 at room temperature. High-resolution Si 2p photoemission spectra, which unambiguously resolve oxide components [Si¹⁺, Si²⁺, Si³⁺ and Si⁴⁺], were successfully measured requiring only 43 s per spectrum. We found that the Si⁴⁺ species gradually increases to reach the oxide thickness of 0.57 nm just after the saturation of Si¹⁺, Si²⁺ and Si³⁺ species with a translational energy of 2.9 eV.     

The accurate measurement of weak three-photon annihilation by a simple triple coincidence technique

The method of triple coincidence is optimized for the detection of the orthopositronium decay. Two positron sources 86-Ge and 22-Na, are compared. The influence of sandwich thickness is described and a method for the correction for those effects is given. This work is supported by the International Atomic Energy Agency, Vienna, through research contract 2516/R.B.