CdS／SiO_2半导体玻璃复合材料的低频Raman散射光谱研究

ＣｄＳ／ＳｉＯ＿２半导体玻璃复合材料的低频Ｒａｍａｎ散射光谱研究王凯旋，隗罡，黄建滨，戴庆红，赵壁英，桂琳琳，谢有畅，唐有祺（北京大学物理化学研究所北京１００８７１）ＡＳｔｕｄｙｏｆＣｄＳＳｅｍｉｅｏｎｄｕｃｔｏｒｉｎＳｉｌｉｃａＧｌａｓｓｅｓｂｙＬ...     

原卟啉（PP）和血卟啉（HP）对DNA空间结构微观光敏损伤的特征

原卟啉（ＰＰ）和血卟啉（ＨＰ）对ＤＮＡ空间结构微观光敏损伤的特征许以明，张志义（中国科学院生物物理研究所北京１００１０１）ＣｈａｒａｃｔｅｒｏｆＭｉｃｒｏｃｏｓｍｉｃａｎｄＰｈｏｔｏｓｅｎｓｉｔｖｅＤａｍａｇｅｏｆＰＰａｎｄＨＰｔｏＴｈｅｓｐａｃｅＳ...     

拉曼光谱在医学上的应用（Ⅱ）

拉曼光谱在医学上的应用（Ⅱ）余国滔（北京大学生命科学学院北京１００８７１）ＢｉｏｍｅｄｉｃａｌＡｐｐｌｉｃａｔｉｏｎｓｏｆＲａｍａｎＳｐｅｃｔｒｏｓｃｏｐｙ（Ⅱ）ＹｕｅＫｗｏｋｔｏ（ＣｏｌｅｇｅｏｆＬｉｆｅＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓ...     

关于半导体极薄层超晶格拉曼散射特征的研究

关于半导体极薄层超晶格拉曼散射特征的研究杨昌黎，张树霖（北京大学物理系北京１００８７１）Ｒ．Ｐｌａｎｅｌ（ＬａｂｏｒａｔｉｒｅｄｅＭｔｃｒｏｓｔｒｕｃｔｕｓｅｄｅｔｄｅＭｉｃｒｏｅｌｅｃｔｒｏｎｉｑｕｅＣｅｎｔｒｅＮａｔｉｏｎａｌｄｅｌａＲｅｃｈｅｒ...     

碳纳米管拉曼光谱的温度效应

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评述文章扫描(英文)

１ＴｈｅｏｒｙｏｆＢｏｓｅ－Ｅｉｎｓｔｅｉｎｃｏｎｄｅｎｓａｔｉｏｎｉｎｔｒａｐｐｅｄｇａｓｅｓ（ＦｒａｎｃｏＤａｌｆｏｖｏ,ＳｔｅｆａｎｏＧｉｏｒｇｉｎｉ,ＬｅｖＰ．Ｐｉｔａｅｖｓｋｉｉｅｔａｌ．Ｒｅｖ．Ｍｏｄ．Ｐｈｙｓ．,１９９９,７１：４６３—５１２）２Ｔｏｐ－ｑｕａｒｋｃｏｎｄｅｎｓａｔｉｏｎ（Ｇ．Ｃｖｅｔｉｃ．Ｒｅｖ．Ｍｏｄ．Ｐｈｙｓ．,１９９９,７１：５１３—５７４）３ＰｒｅｃｉｓｉｏｎｔｅｓｔｓｏｆｔｈｅｅｌｅｃｔｒｏｗｅａｋｉｎｔｅｒａｃｔｉｏｎａｔｔｈｅＺｐｏｌｅ（Ｍ．Ｍａｒｔ…     

Optical Associative Memory Based on Double Phase Conjugation Using Bi_（12）TiO_（20） Photorefractive Fi

ＯｐｔｉｃａｌＡｓｓｏｃｉａｔｉｖｅＭｅｍｏｒｙＢａｓｅｄｏｎＤｏｕｂｌｅＰｈａｓｅＣｏｎｊｕｇａｔｉｏｎＵｓｉｎｇＢｉ＿（１２）ＴｉＯ＿（２０）ＰｈｏｔｏｒｅｆｒａｃｔｉｖｅＦｉｂｅｒ￥ＬＩＵＳｈｕｔｉａｎ（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃｓ，...     

BGO晶体的布里渊散射与弹性系数测量

ＢＧＯ晶体的布里渊散射与弹性系数测量刘金全＊陈浩＊刘玉龙（中国科学院物理研究所北京１０００８０）（＊北京大学北京１００８７１）肖季驹（香港城市大学物理及材料科学系）ＥｌａｓｔｉｃＣｏｎｓｔａｎｔｓｏｆＢＧＯｂｙＢｒｉｌｏｕｉｎＳｃａｎｔｅｒｉｎｇＬｉ...     

Theoretical Analysis and Experimental Research on Recordable Compact Disc with Dye Material

ＴｈｅｏｒｅｔｉｃａｌＡｎａｌｙｓｉｓａｎｄＥｘｐｅｒｉｍｅｎｔａｌＲｅｓｅａｒｃｈｏｎＲｅｃｏｒｄａｂｌｅＣｏｍｐａｃｔＤｉｓｃｗｉｔｈＤｙｅＭａｔｅｒｉａｌ￥ＷＡＮＧＳｈｉｙｏｎｇ；ＷＡＮＧＳｈｉｊｉｅ（ＳＡＳＴＤＯＤＣｏ．Ｌｔｄ．，Ｓｈｅｎｚｈ...     

一类新颖含C60复合材料的合成及其光限制效应的研究

报道了在Ｃ６０与ＮＨ２（ＣＨ２）３Ｓｉ（ＯＣ２Ｈ５）３中的胺基反应生成Ｃ６０－ＮＨ２（ＣＨ２）３Ｓｉ（ＯＣ２Ｈ５）３物质后引入ｒ－缩水甘油醚基丙基三甲氧基硅烷「ＣＨ２ＯＣＨＣＨ２ＯＣＨ２ＣＨ２ＣＨ２Ｓｉ（ＯＣＨ３）３，３－Ｇｌｙｃｉｄｏｘｙｐｒｏｐｌｔｒｉｍｅｔｈｏｘｙｓｉｌａｎｅ，简称ＫＨ５６０」与二甲基二乙氧基硅烷「（ＣＨ３）２Ｓｉ（ＯＣ２Ｈ５）２，Ｄｉｅｔｈｏｘｙｄｉｍｅｔｈｙｌｓｉｌａｎｅ     

Formations and morphological stabilities of ultrathin CoSi₂ films

In this paper we investigate the formations and morphological stabilities of Co-silicide films using 1-8-nm thick Co layers sputter-deposited on silicon(100) substrates.These ultrathin Co-silicide films are formed via solid-state reaction of the deposited Co films with Si substrate at annealing temperatures from 450℃ to 850℃.For a Co layer with a thickness no larger than 1 nm,epitaxially aligned CoSi2 films readily grow on silicon(100) substrate and exhibit good morphological stabilities up to 600℃.For a Co layer thicker than 1 nm,polycrystalline CoSi and CoSi2 films are observed.The critical thickness below which epitaxially aligned CoSi2 film prevails is smaller than the reported critical thickness of the Ni layer for epitaxial alignment of NiSi2 on silicon(100) substrate.The larger lattice mismatch between the CoSi2 film and the silicon substrate is the root cause for the smaller critical thickness of the Co layer.     

Formation and magnetic properties of the silicon-cobalt interface

Formation of the Si/Co interface and its magnetic properties have been studied by high-resolution photoelectron spectroscopy with synchrotron radiation. The experiments have been performed in situ in superhigh vacuum (5 × 10^?10 Torr) with coating thicknesses up to 2 nm. It has been found that, in the initial stage of silicon deposition on the surface of polycrystalline cobalt maintained at room temperature, ultrathin layers of the Co₃Si, Co₂Si, CoSi, and CoSi₂ silicides are formed. The three last phases are nonmagnetic, and their formation gives rise to fast decay of magnetic linear dichroism in photoemission of Co 3p electrons. At deposition doses in excess of ～0.4 nm Si, a film of amorphous silicon grows on the sample surface. It has been established that the Si/Co interphase boundary is stable at temperatures up to ～250°C and that further heating of the sample brings about escape of amorphous silicon from the sample surface and initiates processes involving silicide formation.     

Morphological instabilities of a thin film on a Penrose lattice: A Monte Carlo study

We computed by a Monte Carlo method derived from the solid on solid model, the thermal relaxation of a polycrystalline thin film deposited on a Penrose lattice. The thin film was modeled by a 2-dimensional array of elementary domains, which have each a given height. During the Monte Carlo process, the height of each of these elementary domains is allowed to change as well as their crystallographic orientation. After equilibrium is reached at a given numerical temperature, all elementary domains have changed their orientation into the same one and small islands appear, preferentially on the domains of the Penrose lattice located in the center of heptagons. This method is a numerical approach to study the influence of the substrate and its defects on the islanding process of polycrystalline films.     

Formations and morphological stabilities of ultrathin CoSi2 films

In this paper we investigate the formations and morphological stabilities of Co-silicide fihns using 1-8-nm thick Co layers sputter-deposited on silicon （100） substrates. These ultrathin Co-silicide films are formed via solid-state reaction of the deposited Co films with Si substrate at annealing temperatures from 450 ℃ to 850 ℃. For a Co layer with a thickness no larger than i nm, epitaxially aligned CoSi2 films readily grow on silicon （100） substrate and exhibit good morphological stabilities up to 600 ℃. For a Co layer thicker than 1 nm, polycrystalline CoSi and CoSi2 films are observed. The critical thickness below which epitaxially aligned CoSi2 film prevails is smaller than the reported critical thickness of the Ni layer for epitaxial alignment of NiSi2 on silicon （100） substrate. The larger lattice mismatch between the CoSi2 film and the silicon substrate is the root cause for the smaller critical thickness of the Co layer.     

Magnetic properties of Co–Si alloy clusters

We have investigated the electronic structure and the magnetic properties of Co–Si alloy clusters using ab initio spin-polarized density functional calculations. The possible CoSi₂, CoSi, and Co₂Si phase clusters with oblique hexagon prism, icosahedron, and cuboctahedron structures are introduced. The CoSi phase cluster with icosahedron structure has the largest binding energy and amount of charge transfer. We found that HOMO-LUMO gap, magnetic moment, and spin polarization for the Co–Si alloy clusters with icosahedron structure increase with Co concentration. The Si atoms in the CoSi phase with icosahedron structure have negative magnetic moment.     

多壁碳纳米管薄膜的压阻效应研究

对多壁碳纳米管薄膜的压阻效应进行了研究. 实验所用的多壁碳纳米管用热灯丝化学气相沉积法合成, 压阻效应用三点弯曲法测量. 研究发现: 在室温下与500微应变内, 原始的多壁碳纳米管薄膜无明显压阻效应, 而经化学修饰处理的碳纳米管膜的压阻因子最高可达120左右, 大大超过多晶硅(Si)在35°C时的压阻因子30, 并且压阻因子与制备方法密切相关. 重点讨论了多壁碳纳米管薄膜产生压阻效应的机制.     

氢气稀释比例对多晶硅薄膜微观结构和沉积特性的影响

利用电感耦合等离子体增强化学气相沉积法(ICP-PECVD)直接在普通玻璃衬底上低温沉积多晶硅薄 膜,主要研究了不同氢气稀释比例对薄膜沉积特性和微观结构的影响。采用 X 射线衍射仪(XRD)、拉曼光谱仪和 扫描电子显微镜(SEM)表征了在不同氢气比例条件下所制备多晶硅薄膜的微结构、形貌,并对不同条件下样品的 沉积速率进行了分析。实验结果表明：随着混合气体中硅烷比例的增加,薄膜的沉积速率不断增加;晶化率先增 加,后减小;当硅烷含量为4.8%时,晶化率达到最大值67.3%。XRD 和 SEM 结果显示多晶硅薄膜在普通玻璃衬 底上呈柱状生长,且晶粒排列整齐、致密,这种结构可提高载流子的纵向迁移率,有利于制备高效多晶硅薄膜太阳能电池。     

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Polycrystalline silicon thin film formation from inductively coupled plasma enhanced chemical vapor deposition system was studied. The dilution effect of H₂ on film deposition was discussed. The X-ray diffractometry, Raman spectra and scanning electron microscope measurement were carried out to analyze the influence of H₂ on the microstructures and the topography of polycrystalline silicon thin films. The optimum conditions for polycrystalline silicon thin films deposition were also discussed. The results indicated that polycrystalline silicon thin films with columnar structure crystals were fabricated on glass substrate. The deposition rate exhibited monotonic increase with Silane ratio R, a maximum deposition rate of 0.65nm⋅s^-1 was obtained. However, the crystal volume fraction of polycrystalline silicon thin films initially increased from 60.5% to 67.3%, and then slightly decreased with the increase of R. Therefore, the crystal has a maximum value of 67.3% at R=4.8%. The polycrystalline silicon thin films had a compact and well-arranged structure at this ratio. This structure can also increase carrier mobility and improve the efficiency of solar cells.     

多晶氧化物薄膜及复合膜系应力模型

基于膜层结构的弛豫现象,建立了一个多晶膜的应力演化模型,并通过线性组合给出了复合膜的生长应力模型。利用双光束基底曲率测量装置实时测量了电子束蒸发氧化铪、氧化硅多晶膜及其复合膜的应力演化过程,并对测量结果进行了拟合分析。     

用于彩色滤光片的低阻低应力ITO透明导电膜

探讨了用于彩色滤光片的低电阻和低压应力的ITO透明导电膜工艺。用磁控溅射方法在不同温度的衬底上制备了ITO薄膜。研究了膜形衬底温度与膜结晶化程度的关系,以及膜形衬底温度对膜电阻和压应力的影响。对不同衬底温度下形成的ITO薄膜进行了退火处理,并对退火后的ITO薄膜的电阻和压应力特性进行了分析。结果表明,采用室温沉积非晶态ITO膜,在真空退火下可获得低电阻、低压应力的多晶相ITO膜。