Pd－Ag－Si合金膜中的亚稳相

利用透射电子显微镜（ＴＥＭ）对Ｐｄ－Ａｇ－Ｓｉ合金膜的亚稳相进行了研究。结果表明，真空蒸发的Ｐｄ－Ａｇ－Ｓｉ合金膜由粒度均匀的纳米晶粒组成，具有ｆｃｃ结构。经不同温度退火后，在薄膜的局部区域析出了未知结构的亚稳相。利用电子衍射图确定了这些亚稳相的结构。     

Pd—Ag—Si合金膜中的亚稳相

利用透射电子显微镜（ＴＥＭ）对Ｐｄ－Ａｇ－Ｓｉ合金膜的亚稳相进行了研究，结果表明，真空蒸发的Ｐｄ－Ａｇ－Ｓｉ合金膜由粒度的均匀的纳米晶粒组成，具有ｆｃｃ结构，经不同温度退火后，在薄膜的局部区域析出了未知结构的亚稳相。利用电子衍射图确定了这些亚稳相的结构。     

新型复相陶瓷刀具材料JX－2－Ⅰ的界面结构及其对材料性能的影响

本文利用ＴＥＭ研究了新型复相陶瓷刀具材料Ｊｘ－２－Ⅰ的界面结构，结果表明，在Ｊｘ－２－Ⅰ中Ａｌ＿２Ｏ＿３／ＳｉＣｗ（氧化铝／碳化硅晶须）界面和Ａｌ＿２Ｏ＿３／ＳｉＣｐ（碳化硅颗粒）界面结合良好，形成了具有较高强度的微观结构；发现在ＳｉＣｗ、ＳｉＣｐ和Ａｌ＿２Ｏ＿３晶粒上均有位错产生，在ＳｉＣｐ和Ａｌ＿２Ｏ＿３上有孪晶产生；分析表明，位错和孪晶的产生均吸收大量的断裂能，提高材料的断裂韧性，改善ＪＸ－２－Ⅰ材料的整体性能。     

新型陶瓷刀具材料JX－2－I界面结构的实验研究

利用ＴＥＭ和电子衍射图谱分析，研究了新型陶瓷刀具材料ＪＸ－２－Ｉ的界面微观结构。ＴＥＭ分析表明，ＪＸ－２－Ｉ刀具材料的界面结合状态较好，Ａｌ＿２Ｏ＿３／ＳｉＣｗ界面上形成了具有较高强度的“钢筋混凝土”结构，在Ａｌ＿２Ｏ＿３／ＳｉＣｗ和Ａｌ＿２Ｏ＿３／ＳｉＣｐ界面上没有剧烈的化学反应发生；通过ＴＥＭ和电子衍射图分析，发现在Ａｌ＿２Ｏ＿３的晶粒边界上有尖晶石（ＭｇＡｌ＿２Ｏ＿４）生成，这有利于控制Ａｌ＿２Ｏ＿３晶粒的长大，提高复合材料的强度。     

Pd／W／Si（111）双层膜形成硅化物的XRD研究

对Ｐｄ／Ｗ／Ｓｉ（１１１）双层膜系统在稳定退火条件下形成硅化物作了研究，实验结果表明：Ｐｄ／Ｗ／Ｓｉ（１１１）双层膜中Ｗ单层膜起了阻挡Ｐｄ－Ｓｉ原子互扩散的作用，随着退火温度的升高，Ｐｄ，Ｗ，Ｓｉ原子的互扩散不断进行，硅化物首先在Ｗ／Ｓｉ界面处生成。由于ＰｄＳｉｘ晶粒不断地长大，将Ｗ原子推到薄膜的外层，形成了Ｐｄ－Ｗ原子的分布反转。这样在Ｓｉ衬底的界面处形成了硅化物的浅接触，而薄膜的外层形成了...     

纳米硅薄膜界面结构的微观特征

对使用等离子体增强化学汽相沉积法（ＰＥＣＶＤ）制备的纳米硅薄膜（ｎｃ－Ｓｉ：Ｈ），使用ＨＲＥＭ及ＳＴＭ技术观测了其显微结构，给出大量的界面结构图象．首次获得有关晶粒及界面区中原子的分布情况．使我们认识到ｎｃ－Ｓｉ：Ｈ膜中界面区内的硅原子仍然是具有短程有序性并不是完全无序的．     

纳米硅薄膜分形凝聚模型

从分析纳米硅（ｎｃ－Ｓｉ：Ｈ）薄膜生长过程的特点出发，提出与扩散限制凝聚（ＤＬＡ）模型不同的ｎｃ－Ｓｉ：Ｈ薄膜分形凝聚模型：扩散与反应限制凝聚（ＤＲＬＡ）模型．获得的结果与实验结果符合得很好．ｎｃ－Ｓｉ：Ｈ薄膜是利用等离子体增强气相淀积方法制备的．文中讨论了ｎｃ－Ｓｉ：Ｈ薄膜的结构特点与分形凝聚之间的关系．     

非晶Ni88P12合金薄膜的AFM和STM研究

本文报导利用ＳＴＭ（Ｓｃａｎｎｉｎｇ Ｔｕｎｎｅｌｉｎｇ Ｍｉｃｒｏｓｃｏｐｅ）和ＡＦＭ（Ａｔｏｍｉｃ Ｆｏｒｃｅ Ｍｉｃｒｏｓｃｏｐｅ）对化学沉积的非晶及高温晶化后的Ｎｉ８８Ｐ１２合金薄膜表明的形貌进行了研究，观察到非晶合金膜是由纳米大小的微粒聚成微米大小的颗粒构成的，晶化后颗粒长大变为晶粒。     

nc—Si：H／c—Si量子点二极管中的共振隧穿特性分析

采用常规ＰＥＣＶＤ工艺，在Ｎ型单晶硅（ｃ－Ｓｉ）衬底上沉积薄层纳米Ｓｉ（ｎｃ－Ｓｉ）膜，并进而制备了ｎｓ－Ｓｉ：Ｈ／ｃ－Ｓｉ量子点二极管。在１０￣１００Ｋ温度范围内实验研究了该结构的σ－Ｖ和Ｉ－Ｖ特性。结果指出，当反身偏压为－７￣－９Ｖ时，无论在σ－Ｖ还是在Ｉ－Ｖ特性曲线上都观测到了近乎等间距的量子化台阶，此起因于在ｎｃ－Ｓｉ：Ｈ膜中具有无序排布且粒长大小不一的Ｓｉ微晶粒子，由于微晶粒子中能级的量     

nc-Si∶H/c-Si量子点二极管中的共振隧穿特性分析

采用常规ＰＥＣＶＤ工艺，在Ｎ型单晶硅（ｃ－Ｓｉ）衬底上沉积薄层纳米Ｓｉ（ｎｃ－Ｓｉ）膜，并进而制备了ｎｃ－Ｓｉ∶Ｈ／ｃ－Ｓｉ量子点二极管．在１０～１００Ｋ温度范围内实验研究了该结构的σ－Ｖ和Ｉ－Ｖ特性．结果指出，当反向偏压为－７～－９Ｖ时，无论在σ－Ｖ还是在Ｉ－Ｖ特性曲线上都观测到了近乎等间距的量子化台阶，此起因于在ｎｃ－Ｓｉ∶Ｈ膜中具有无序排布且粒径大小不一的Ｓｉ微晶粒中，由于微晶粒中能级的量子化而导致的共振隧穿现象．如果进一步改进膜层生长工艺，以制备出具有趋于有序排布、尺寸均匀和粒径更小的Ｓｉ微晶粒的     

近距离升华法制备Bi催化纳米晶CdTe薄膜的表征

采用近距离升华法(Close-Spaced-Sublimation,CSS)引入Bi催化剂成功制备出了具有纳米线、近阵列排布的纳米棒等形貌的纳米晶CdTe薄膜.并利用X射线衍射(XRD)、扫描电子显微镜(SEM)、紫外可见分光光度计等研究了薄膜的结构、表面形貌和光学性能.讨论了CdTe纳米结构可能的生长机制.

Abstract：

Bi-catalyzed nanocrystalline CdTe films were prepared by close spaced sublimation (CSS) technique successfully.These nanocrystalline CdTe films had surface appearance of nanowires or a similar array arrangement nanorod.The structure,the surface topograph and the optical properties of these films were studied using X-ray diffraction(XRD),scanning electron microscopy(SEM) and ultroviolet-visible (UV-VIS) spectrophotometer.And the possible growth mechanisms of these nanostructures were discussed.     

不同衬底上纳米晶CdTe薄膜的低温制备及光性能研究

CdTe nanocrystalline thin films have been prepared on glass, Si and Al2O3 substrates by radio-frequency magnetron sputtering at liquid nitrogen temperature. The crystal structure and morphology of the films were charac-terized by X-ray diffraction （XRD） and field-emission scanning electron microscopy （FESEM）. The XRD examinations revealed that CdTe films on glass and Si had a better crystal quality and higher preferential orientation along the （111） plane than the Al2O3. FESEM observations revealed a continuous and dense morphology of CdTe films on glass and Si substrates. Optical properties of nanocrystalline CdTe films deposited on glass substrates for different deposited times were studied.     

Properties of CdTe nanocrystalline thin films grown on different substrates by low temperature sputtering

CdTe nanocrystalline thin films have been prepared on glass, Si and Al2O3 substrates by radio-frequency magnetron sputtering at liquid nitrogen temperature. The crystal structure and morphology of the films were characterized by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). The XRD examinations revealed that CdTe films on glass and Si had a better crystal quality and higher preferential orientation along the (111) plane than the Al2O3. FESEM observations revealed a continuous and dense morphology of CdTe films on glass and Si substrates. Optical properties of nanocrystalline CdTe films deposited on glass substrates for different deposited times were studied.     

热丝化学气相沉积法低温制备纳米晶态碳化硅薄膜

采用热丝化学气相沉积(HFCVD)技术以甲烷(CH4)和硅烷(SiH4)作为源反应气体在Si(111)衬底上合成了纳米晶态SiC薄膜。通过X射线衍射(XRD)、扫描电镜(SEM)、高分辨透射电镜(HRTEM)以及光致发光(PL)检测技术对薄膜的晶体结构、表面形貌和PL特性进行了分析和表征。结果表明，在较低的衬底温度下所沉积的薄膜是由镶嵌于非晶SiC网络中的晶态纳米SiC构成。纳米晶粒平均尺寸约为6nm。室温下用HeCr激光激发样品，观到薄膜发出波长位于400～550nm范围内可见光辐射。     

Crystallization and Transport Properties of Amorphous Cr-Si Thin Film Thermoelectrics

We studied the thermoelectric properties, crystallization, and stability of amorphous and nanocrystalline states in Cr-Si composite films. Amorphous films, prepared by magnetron sputtering, were transformed into the nanocrystalline state by annealing with in situ thermopower and electrical resistivity measurements. We have found that the amorphous state is stable in these film composites to about 550 K. Prior to crystallization, the amorphous films undergo a structural relaxation, detected by peculiarities in the temperature dependences of the transport properties, but not visible in x-ray or electron diffraction. The magnitude and temperature dependences of electrical conductivity and thermopower indicate that electron transport in the amorphous films is through extended states. The amorphous films are crystallized at annealing temperatures above 550 K into a nanocrystalline composite with an average grain size of 10–20 nm.     

PECVD法制备纳米晶硅薄膜的研究进展

简要介绍了纳米晶硅薄膜的微结构表征方法,重点讨论了PECVD制备方法中工艺参数对薄膜结构的影响,并探讨了氢在薄膜形成和生长中的作用。通过优化氢稀释率、衬底温度、反应气压、激励功率和激发频率等工艺参数可提高纳米晶硅薄膜的晶化率并改善薄膜质量。结合喇曼光谱、X射线衍射谱、傅里叶红外光谱和高分辨透射电镜等表征方法可深入研究薄膜形成机理,对进一步探索薄膜光电特性有重要意义。分析了等离子体化学气相沉积(PECVD)制备方法中各工艺参数对薄膜质量和沉积速率的影响,指出其存在的问题,并探寻了今后的研究方向。     

Influence of Deposition Parameters on the Morphology, Structural, and Optical Properties of ZnSe Nanocrystalline Thin Films

Zinc selenide (ZnSe) nanocrystalline thin films were prepared by using chemical bath deposition at different ammonia concentrations and different deposition temperatures. The structural and optical properties of ZnSe nanocrystalline thin films were investigated as a function of the ammonia concentration in precursors or the deposition temperature using scanning electron microscopy, energy-dispersive spectrometry, x-ray diffraction measurements, and ultraviolet (UV)–visible spectrophotometry measurements. The results reveal that the ZnSe thin films are composed of a large number of uniform spherical particles. Each spherical particle contains several nanocrystals 5 nm to 7 nm in crystallite size. An increase in both the average diameter of the spherical particles and the crystallite size of the nanocrystals occurs with an increase in ammonia concentration and/or deposition temperature. The Se/Zn atom ratios in the ZnSe thin films increase and the optical band gaps, E _g, of the ZnSe thin films decrease with an increase in ammonia concentration or deposition temperature. The kinetics and reaction mechanism of the ZnSe nanocrystalline thin films during deposition are discussed.     

Thickness dependent physical properties of chemically deposited nanocrystalline MgSe thin films deposited at room temperature by solution growth method

Chemical bath deposition method has been employed to deposit nanocrystalline magnesium selenide thin films of thickness 104–292 nm onto glass substrates at room temperature. The deposition bath consists of magnesium chloride, triethanolamine (TEA) and selenium dioxide. The as deposited films were characterized by X-ray diffraction, scanning electron microscopy (SEM), atomic force microscopy (AFM), optical absorption, electrical resistivity and thermo-emf measurements. The X-ray diffraction (XRD) studies revealed that the crystallinity of the magnesium selenide thin film increases with thickness. SEM studies reveal that MgSe films exhibit uniform distribution of round shaped grains over the entire substrate surface.The optical band-gap and electrical resistivity of MgSe film decrease as the film thickness increases. Such type of dependence is attributed to the quantum size effect that is observed in nanocrystalline semiconductors.The thermo-emf measurement confirms its p-type conductivity.     

Fabrication of heterostructures based on layered nanocrystalline silicon carbide polytypes

The study demonstrates the possibility of forming heterostructures consisting of nanocrystalline SiC layers of the cubic 3C polytype (the lower layer on the substrate) and the rhombohedral 21R polytype (the upper layer) by direction deposition of nanocrystalline SiC layers onto a substrate subjected to gradient heating. The structure and order of arrangement of the SiC layers are analyzed in detail by X-ray diffraction studies, femtosecond photoluminescence measurements, and optical spectroscopy. The nature of the peaks observed in the photoluminescence, optical reflectance, and absorption spectra is discussed.     

Synthesis and characterization of CdSe nanocrystalline thin films deposited by chemical bath deposition

Cadmium selenide (CdSe) nanocrystalline thin films were prepared by chemical bath deposition (CBD) using ammonia and triethanolamine (TEA) as complexing agents, cadmium chloride and sodium selenosulphate as the sources of Cd²⁺ and Se^2? ions, respectively. The structural and optical properties of CdSe nanocrystalline thin films were investigated as a function of the sodium selenosulphate concentrations or ammonia concentrations in precursors using scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) measurements, transmission electron microscopy (TEM) and UV–visible spectrophotometer measurements. The results reveal that the CdSe thin films are in the pure cubic phase, which composed of a large number of uniform spherical particles. Each spherical particle contains many nanocrystals 3–10 nm in crystallite size. An increase in both the average diameter of the spherical particles and the crystallite size of the nanocrystals occurs with an increase in ammonia concentrations. The Se/Cd atom ratios of CdSe thin films firstly increase and then decrease with an increase in ammonia concentration or sodium selenosulphate concentration. The optical band gap of CdSe thin films decrease with an increase in ammonia concentrations. The kinetics and reaction mechanism of the CdSe nanocrystalline thin films during deposition are discussed.