XUV成像系统中像传递函数研究用的Si刻蚀膜

 研制具有网格或条状图形的Si刻蚀膜靶，用于XUV系统中像传递函数的研究。在自截止腐蚀工艺制备Si平面薄膜的基础上，结合离子束刻蚀工艺，获得刻蚀深度为1.0 μm左右，网格尺寸为25 μm×25 μm，或条状线宽为5 μm的Si刻蚀膜；测量了Si刻蚀膜的形貌和刻蚀深度；研究了离子束刻蚀参数对图形形貌的影响。并介绍采用两种靶型获得的像传递函数信息。     

CF_4/Ar/O_2等离子体对熔石英元件的修饰工艺

采用感应耦合等离子体刻蚀技术,以CF4/Ar/O2为反应气体对熔石英元件表面进行修饰,研究并分析了CF4和Ar流量对刻蚀速率、熔石英表面粗糙度和微观形貌的影响。结果表明,CF4化学刻蚀与Ar的物理轰击对熔石英样品表面修饰效果存在一定竞争关系,当它们达到平衡时表面粗糙度最小。通过对不同流量气体刻蚀过后熔石英表面粗糙度和光学显微形貌分析获得了较为理想的气流量配比,该研究为反应等离子体修饰熔石英光学元件以获得较高光学性能提供工艺参考。     

水浴条件下YAG倍频、三倍频激光切割Si片比较

对Nd∶YAG固体激光器倍频、三倍频激光输出在空气和水浴环境下刻蚀Si片进行了研究,分析了刻蚀速率和样品表面形貌,得出了在355 nm刻蚀波长下,水浴环境中,刻蚀速率最快,刻槽宽度最小,小于10 μm的实验结论,为工业应用提供参考.     

熔石英元件HF刻蚀的实验研究

为深入了解熔石英元件化学刻蚀过程,研究了HF刻蚀反应机理、HF刻蚀工艺参数以及刻蚀对表面质量的影响规律。通过控制变量法,获得刻蚀速率随HF浓度、刻蚀温度以及NH4F浓度的变化规律。对刻蚀不同深度后的元件表面粗糙度、形貌、杂质含量以及激光损伤阈值进行了检测,实验结果表明:刻蚀速率受多种因素共同影响,其中HF浓度的促进作用最为显著;刻蚀后的熔石英表面形貌复杂,有横向、纵向、拖尾等形式的划痕,以及坑点、杂质等缺陷,其中横向划痕和纵向划痕占据了缺陷部分的主体,主要杂质铈元素随刻蚀时间的增长不断减少;激光损伤阈值测量实验表明,通过HF刻蚀将元件损伤阈值提高了59.6%。     

基于壁面反射增强模型的熔石英刻蚀形貌形成机理研究

大气等离子体刻蚀是一种非接触式、材料去除可控的加工方法,在光学元件的高精度加工中具有广泛的应用前景。但是大气等离子体刻蚀后元件存在表面形貌恶化的问题,严重影响元件的性能和使用寿命。进行氢氟酸刻蚀实验,证明了元件表面形貌的恶化是由氟碳化合物和表面凹坑微结构两个原因引起的。为了解释表面凹坑微结构的形成,提出基于micro-mask壁面反射增强理论的凹坑形成模型,并开展了样品表面旋涂金纳米颗粒充当micro-mask的刻蚀实验。实验结果验证了micro-mask壁面反射增强模型的正确性,为解决大气等离子体刻蚀后元件表面形貌恶化问题提供了新的思路和方法。     

HTS台阶边缘结特性和制作的实验研究

本文用原子力显微镜（ＡＦＭ）对有不同伏安特性的台阶边缘结之台阶形貌进行了仔细测量．结果表明：台阶边缘晶界结特性受非平面衬底离子束刻蚀剖面细节的影响．文中对刻蚀剖面形貌的细节对结性能的影响进行了分析，并讨论了台阶结制作工艺重复性差，成品率低的原因     

准分子激光电化学刻蚀金属的研究

为了探寻准分子激光电化学刻蚀工艺的特性,采用功率密度大的248nm准分子激光聚焦照射浸在溶液中的金属表面,实现了一种激光电化学刻蚀复合工艺。在实验的基础上,通过对激光电化学刻蚀金属和硅的基本形貌进行比较和分析,研究了该工艺的工艺特性。研究结果表明,该复合工艺为激光直接刻蚀和激光热诱导电化学刻蚀。其中激光热诱导电化学刻蚀是通过激光的光热效应和由激光诱导的冲击波来实现对腐蚀液和材料的冲击、微搅拌等作用的。     

大面积高深宽比硅微通道板阵列制作

利用光辅助电化学刻蚀方法,在厚度为425μm的5英寸硅片上,制作成深宽比达50以上的微通道板阵列结构.理论分析了影响微孔阵列形貌形成的关键因素,并结合实验条件,通过调整刻蚀电压值和根据莱曼模型修正实验电流值得到理想的孔壁形貌.结果表明,相比于目前在硅基上制作高深宽微结构的几种技术,光辅助电化学刻蚀方法能够实现孔壁光滑、面积大和深宽比高的微通道板阵列结构的低成本制作.     

6H-SiC单晶的激光刻蚀及光谱分析（英文）

激光微加工是半导体精密加工的一个有效方法。对于碳化硅(SiC)单晶,使用紫外波段激光可以获得对入射能量最大的吸收效率。使用355nm全固态激光器对6H-SiC单晶进行刻蚀。同时将样品置于不同的介质下以探究最优加工条件。使用拉曼光谱表征激光刻蚀后的SiC表面。刻蚀后表面主要由无定形硅及纳米晶石墨组成,对于空气下刻蚀的SiC晶片,无定形硅主要分布于刻蚀坑的周围,刻蚀坑内较少。而在液体下刻蚀的样品,无定形硅的空间分布相反。通过分析残留在表面的物质,在另一角度研究了激光刻蚀的反应机理。对于液体辅助的激光加工,以往的研究主要关注液层的厚度及粘度,对液体还原性的研究很少。为确定液体还原性的影响,使用共聚焦激光扫描显微镜及能量色散谱检测了不同液体辅助加工样品的表面形貌及氧含量。结果表明,液体还原性在激光刻蚀过程中有着较大的影响,使用有着还原性的液体作为介质可以有效减少表面氧化并获得更规则的表面形貌。     

6H-SiC单晶的激光刻蚀及光谱分析

激光微加工是半导体精密加工的一个有效方法。对于碳化硅(SiC)单晶,使用紫外波段激光可以获得对入射能量最大的吸收效率。使用355 nm全固态激光器对6H-SiC单晶进行刻蚀。同时将样品置于不同的介质下以探究最优加工条件。使用拉曼光谱表征激光刻蚀后的SiC表面。刻蚀后表面主要由无定形硅及纳米晶石墨组成,对于空气下刻蚀的SiC晶片,无定形硅主要分布于刻蚀坑的周围,刻蚀坑内较少。而在液体下刻蚀的样品,无定形硅的空间分布相反。通过分析残留在表面的物质,在另一角度研究了激光刻蚀的反应机理。对于液体辅助的激光加工,以往的研究主要关注液层的厚度及粘度,对液体还原性的研究很少。为确定液体还原性的影响,使用共聚焦激光扫描显微镜及能量色散谱检测了不同液体辅助加工样品的表面形貌及氧含量。结果表明,液体还原性在激光刻蚀过程中有着较大的影响,使用有着还原性的液体作为介质可以有效减少表面氧化并获得更规则的表面形貌。     

Synthesis and characterization of nano-sepiolite by solvothermal method

Nano-sepiolite with novel morphology has been fabricated by solvothermal method in different conditions. The nano-sepiolite was characterized by X-ray fluorescence analysis, X-ray powder diffraction, thermal gravimetry analysis, differential thermal analysis and infrared spectroscopy. Scanning electron microscopy observations revealed that using of solvothermal route led to nano-wires of sepiolite. The reactions have been performed in several conditions to find out the role of different factors such as the aging time and temperature of the reaction in the solvothermal on the size and morphology of the nano-structures.     

Interfacial pattern formation far from equilibrium

Over the past few years diffusion-controlled systems have been shown to share a common set of interfacial morphologies. The singular nature of the microscopic dynamics of surface tension and kinetic growth far from equilibrium are critical to morphology selection, with special importance attributed to the anisotropy of these effects. The morphologies which develop can be organized via a morphology diagram according to the driving force and the effective anisotropy. We focus on the properties of the dense-branching morphology (DBM) which appears for sufficiently weak effective anisotropy, and the nature of morphology transitions between the DBM and dendritic growth stabilized by either surface tension or kinetic effects. The DBM is studied in the Hele-Shaw cell, and its structure analyzed by linear stability analysis. A comparison is made between the power spectrum of the structure and the stability analysis. We then provide a detailed account of the morphology diagram and morphology transitions in an anisotropic Hele-Shaw cell. Theoretically the question of morphology transitions is addressed within the boundary-layer model by computing selected velocities as a function of the undercooling for different values of the surface tension and the kinetic term. We argue that the fastest growing morphology is selected whether it is the DBM, surface tension dendrites, or kinetic dendrites. A comparison is made with our experimental results in electrochemical deposition for the correspondence between growth velocities and morphology transitions.     

Nanocomposites Based on Aromatic Polyamide-Imide and Magnesium Hydrosilicate Nanotubes

Structure, morphology, and thermal properties of nanocomposites based on thermally stable poly(diphenyloxydamide-N-phenylphtalimide) (PAI) and layered magnesium hydrosilicate nanotubes (NTs) were studied using thermogravimetric analysis, dynamic mechanical analysis, atomic force microscopy, and differential scanning calorimetry. Thermal stability and glass transition temperature of the composites were shown to exceed those of the PAI matrix. Introduction of NT into the polymer matrix appreciably increased the elasticity and deformability of the composite material. The content of NT was also shown to greatly influence the surface morphology of the PAI-NT composites.     

Quantitative microscopy characterization of hydrous niobium phosphate into bleached cellulose

In this research the spatial distribution characterization of niobium phosphate into bleached cellulose was carried out combining processing and images analysis obtained by SEM and statistical methodologies. The objective is to investigate the deposit composition and phosphate morphology by using complementary analytical techniques. Based on the proposed methodology, parameters of niobium phosphate agglomerates (size and shape) and fiber morphology were evaluated depending on gray-levels (average luminance and fiber type): fiber characteristics (morphology) were measured. For the test method proposed, a specific region of cellulose/NbOPO₄·nH₂O composite was analyzed. This method involves area fraction measuring with a conditional probabilistic analysis. The analyzed fields were divided in different ways, called ‘Scanning’ and as a result, in quantitative terms, the phosphate deposition was described as spatial distribution homogeneous or inhomogeneous. The quantitative microscopy as a non-destructive testing provides relevant information when it is combined with statistic analysis.     

AFM investigation of films based on UV-solidified powder oligoesterdimethacrylate compositions

The morphology, supramolecular structure, and thermal behavior of powder coatings based on UV-solidified oligoesterdimethacrylate powder compositions with and without reactive coreactant bis-styrenated urethane prepared on different substrates have been studied using atomic-force microscopy, X-ray phase analysis, and differential scanning calorimetry. It was found that addition of the reactive coreactant in powder compositions results in homogenization of structure and morphology of coatings and increase in their glass transition temperatures by more than 10 K. The character of their morphology depends also on the conditions of film formation and substrate material. Unmodified coatings formed on a steel substrate exhibit an anisotropic structure, in contrast to the coatings prepared on the PTFE substrate, which are isotropic and represent a homogeneous polymer matrix containing aggregates formed by inclusions of nanoand microdimensions.     

硅晶体表面石墨烯褶皱形貌的分子动力学模拟研究

本文利用分子动力学的方法和模拟退火技术从原子尺度分析研究了Si (100), Si (111)和Si (211)表面单原子层石墨烯的褶皱形貌及其演化特点. 研究表明, 分别置于Si晶体的三种不同原子表面的石墨烯都展现出原子尺度的褶皱形貌. 石墨烯与Si晶体表面原子的晶格失配是引起石墨烯褶皱的主要原因. 研究发现, Si晶体表面石墨烯的褶皱形貌强烈的依赖于退火温度. 石墨烯的褶皱形貌还将直接影响其在Si晶体表面的吸附稳定性. 这些研究结果有助于人们认识基于Si晶体衬底的石墨烯的结构形貌及其稳定性, 为石墨烯的进一步应用提供理论参考.     

Spectroscopic Method for Studying the Morphology of Suspensions

Journal of Applied Spectroscopy - A spectroscopic method for studying the morphology of microsuspensions based on an analysis of the scattering component of electromagnetic radiation passing...     

Preparation of nano-hydroxyapatite particles with different morphology and their response to highly malignant melanoma cells in vitro

To investigate the effects of nano-hydroxyapatite (HA) particles with different morphology on highly malignant melanoma cells, three kinds of HA particles with different morphology were synthesized and co-cultured with highly malignant melanoma cells using phosphate-buffered saline (PBS) as control. A precipitation method with or without citric acid addition as surfactant was used to produce rod-like hydroxyapatite (HA) particles with nano- and micron size, respectively, and a novel oil-in-water emulsion method was employed to prepare ellipse-like nano-HA particles. Particle morphology and size distribution of the as prepared HA powders were characterized by transmission electron microscope (TEM) and dynamic light scattering technique. The nano- and micron HA particles with different morphology were co-cultured with highly malignant melanoma cells. Immunofluorescence analysis and MTT assay were employed to evaluate morphological change of nucleolus and proliferation of tumour cells, respectively. To compare the effects of HA particles on cell response, the PBS without HA particles was used as control. The experiment results indicated that particle nanoscale effect rather than particle morphology of HA was more effective for the inhibition on highly malignant melanoma cells proliferation.     

Image analysis of atmospheric corrosion of field exposure high strength aluminium alloys

The corrosion morphology image acquisition system which can be used in the field was established. In Beijing atmospheric corrosion exposure station, the image acquisition system was used to capture the early stage corrosion morphology of five types of high strength aluminium alloy specimens. After the denoise treatment, wavelet-based image analysis method was applied to decompose the improved images and energies of sub-images were extracted as character information. Based on the variation of image energy values, the corrosion degree of aluminium alloy specimens was qualitatively and quantitatively analyzed. The conclusion was basically identical with the result based on the corrosion weight loss. This method is supposed to be effective to analysis and quantify the corrosion damage from image of field exposure aluminium alloy specimens.     

(001) textured PbTiO3 thin films grown on redopingn-Si by metalorganic chemical vapor deposition under reduced pressure

(001) textured PbTiO₃ thin films have been deposited on (001) redopingn-Si substrates by metalorgnic chemical vapor deposition (MOCVD) under reduced pressure, and the film ferroelectricity has been measured using the substrate as bottom electrode directly. Besides this investigation, a set of analysis including AFM surface morphology, SEM cross section morphology, electron-probe element analysis, XRD 0-20 scan and high temperature X-ray diffraction have been carried out to study the microstructure and phase transition process of the PbTiO₃ thin film.