ZrO2溅射膜的柱状生长机制

气相沉积ZrO2膜常为柱状结构,要更好地控制ZrO2膜性能,需要研究ZrO2膜中柱状结构的形成和演化规律.在射频溅射条件下沉积了ZrO2膜,发现该膜的柱状晶具有{111}面织构,其底层可能还有等轴晶.提出以下柱状晶形成机制在光滑(玻璃)基片上形成的柱状晶源自于在基片表面形成的具有{111}面织构的最初晶核;在较为粗糙(多晶Al2O3)基片表面上形成的柱状晶源自于〈111〉晶向与沉积物质流方向一致的晶核择优生长及随后对其它取向的小晶核的吞噬而形成的晶核群.基片表面粗糙时,由于柱状晶核经过晶核筛选产生,柱状晶底部可能有等轴晶层;若温度较低,出现等轴晶层可能性更大.     

ZrO2膜的相结构与显微组织

本文用X射线衍射和扫描电镜研究了ZrO2膜的晶体结构和显微组织。结果表明ZrO2膜的相结构为立方氧化锆（c-ZrO2），晶粒尺寸细微。发现ZrO2膜中存在具有{111}面织构柱状晶结构，这种结构可用基片负偏压消除。     

卷曲温度对无取向硅钢组织结构及其变化的影响

通过工业试验和金相显微镜、扫描电镜、背散射衍射技术研究了卷曲温度对50W600无取向硅钢热轧板、冷轧板和退火冷轧板的组织结构及其变化的影响. 结果表明,无取向硅钢热轧板→冷轧板→退火冷轧板的织构演变为高斯织构{110}<001>→{111}和{100}面织构→{111}和少量{100}面织构. 卷曲温度从680℃提高到720℃,有利于无取向硅钢热轧板再结晶晶粒形核和长大,退火冷轧板的晶粒尺寸从40.88 mm增加到48.58 mm. 卷曲温度为680℃时,无取向硅钢退火冷轧板中{111}, {100}面织构分别为32.9%和6.1%(j);720℃时,其退火冷轧板中{111}和{100}面织构分别为25.1%和7.9%(j). 卷曲温度从680℃提高到720℃,无取向硅钢退火冷轧板的铁芯损耗从3.94 W/kg降到3.85 W/kg,磁感应强度从1.690 T提高到1.701 T.     

二氧化硅/二氧化锆核壳复合材料的制备及性能

合成了一种新型的二氧化硅/二氧化锆(SiO2/ZrO2)核壳型复合材料。利用异丙醇锆的水解缩合在SiO2微球表面沉积ZrO2层,得到二氧化锆包覆的SiO2/ZrO2核壳型复合氧化物。采用SEM、EDX、XRD等对复合材料的形貌及性质进行表征。利用IR-1红外发射率测量仪测定复合粒子在8～14μm波段的红外发射率。结果显示:该复合物具有明显的核壳结构。随着沉积次数的增加,ZrO2在SiO2表面的含量增加。ZrO2层经高温热处理可分别形成四方和单斜两种晶型。ZrO2层沉积在SiO2表面后,得到的SiO2/ZrO2核壳复合粒子的红外发射率较基底SiO2的有所降低。ZrO2的晶型也影响着复合材料的红外发射性能。ZrO2层为单斜晶的SiO2/ZrO2核壳复合物在8～14μm波段的红外发射率值比ZrO2层为四方晶时的更小。ZrO2层和SiO2球之间的界面作用解释了该复合材料红外发射率降低的原因。     

BaTiO3铁电薄膜在硅基片上的取向生长

采用脉冲激光沉积方法,在硅基片上先沉积MgO或CeO2缓冲层后再制备BaTiO3(BTO)铁电薄膜.通过原位反射高能电子衍射来监测MgO,CeO2缓冲层在硅基片上的生长行为.用X射线衍射测定BTO薄膜的结晶取向.并利用压电响应力显微镜观察了铁电薄膜的自发极化形成的铁电畴.结果表明:BTO薄膜在不同的缓冲层硅基片上以不同的取向生长,在织构的MgO/Si(001)基片上为(001)择优,择优程度与MgO织构品质有关,其中在双轴织构MgO缓冲层上为(001)单一取向;在CeO2(111)缓冲层上为(011)单一取向.(001)取向的BTO薄膜具有更大的面外极化,而(011)取向的BTO薄膜具有更大的面内极化.     

采用二次原位法合成{111}优先取向的NaY沸石膜

采用二次原位水热合成方法在多孔α-Al2O3支撑体上生长出致密连续的{1 1 1}晶面优先取向的NaY型沸石膜.合成液的配比为10SiO2:Al2O3:14Na2O:800H2O,考察了陈化时间、陈化方式和晶化次数等因素对膜微结构的影响.通过XRD和SEM等手段对所制备的膜材料进行了表征,结果表明,一次原位水热晶化得到的膜层不连续,搅拌陈化可得到{111}晶面优先取向的NaY型沸石膜,膜层中晶粒均匀.在相同的合成条件下,搅拌陈化,二次原位水热合成可得到{111}晶面优先取向的致密连续的NaY型沸石膜,膜厚约15 μm.     

用高分辨透射电子显微技术研究0.94(Na1/2Bi1/2)TiO3-0.06BaTiO3的有序结构

用高分辨透射电子显微技术(high resolution transmission electron microscopy, HRTEM)和选区电子衍射(selected electron diffraction, SAED)技术对具有A位复合钙钛矿结构的0.94(Na1/2Bi1/2) TiO3(BNT)-0.06BaTiO3(BNBT6)陶瓷的显微结构进行了深入研究.沿[001],[011]和[111]3个晶带轴方向的SAED花样分析结果表明:A位Bi3 和Na 可以形成2种不同的有序结构──1/2{110}和1/2{111}超结构.据此,建立了BNT的1/2{110}和1/2{111}有序结构模型,其中1/2{110}型有序是由Bi3 层和Na 层沿[110]方向交替排列而形成,1/2{111}型有序是由Bi3 层和Na 层沿[111]方向交替排列而形成.利用多层法,通过计算机模拟了1/2{111}有序结构沿[001],[011]和[111]3个方向的HRTEM像,与实验拍摄的HRTEM像对照,验证了所建立的1/2{111}有序结构模型的正确性.同时,采用快速Fourier变换(fast Fourier transformation, FFT),由1/2(330)和1/2(330)超晶格反射斑点获得的一维晶格像,揭示了沿[110]方向局部Bi3 层和Na 层扭曲导致的位错和反相畴界(anti-phase boundary, APB), APB的存在表明结构中存在着Bi3 层和Na 层沿[110]方向的交替排列,证实BNBT6中存在着1/2{110}有序结构.BNBT6有序结构的HRTEM研究表明:A位Bi3 和Na 的化学有序是导致超晶格反射的主要原因.     

用高分辨透射电子显微技术研究0.94（Na（1/2）Bi（1/2））TiO3–0.06BaTiO3的有序结构

用高分辨透射电子显微技术（high resolution transmission electron microscopy,HRTEM）和选区电子衍射（selected area electron diffraction,SAED）技术对具有A位复合钙钛矿结构的0.94（Na1/2Bi1/2）TiO3（BNT）–0.06BaTiO3（BNBT6）陶瓷的显微结构进行了深入研究。沿[001],[011]和[111]3个晶带轴方向的SAED花样分析结果表明：A位Bi3＋和Na＋可以形成2种不同的有序结构——1/2{110}和1/2{111}超结构。据此,建立了BNT的1/2{110}和1/2{111}有序结构模型,其中1/2{110}型有序是由Bi^3＋层和Na^＋层沿[110]方向交替排列而形成,1/2{111}型有序是由Bi^3＋层和Na^＋层沿[111]方向交替排列而形成。利用多层法,通过计算机模拟了1/2{111}有序结构沿[001],[011]和[111]3个方向的HRTEM像,与实验拍摄的HRTEM像对照,验证了所建立的1/2{111}有序结构模型的正确性。同时,采用快速Fourier变换（fast Fourier transformation,FFT）技术,由1/2（330）和1/2（330）超晶格反射斑点获得的一维晶格像,揭示了沿[110]方向局部Bi3＋层和Na＋层扭曲导致的位错和反相畴界（anti-phase boundary,APB）,APB的存在表明结构中存在着Bi3＋层和Na＋层沿[110]方向的交替排列,证实BNBT6中存在着1/2{110}有序结构。BNBT6有序结构的HRTEM研究表明：A位Bi^3＋和Na^＋的化学有序是导致超晶格反射的主要原因。     

β-SiC晶须缺陷的HREM观察

用高分辨电镜(HREM)观察了β-SiC晶须的微观结构和缺陷,得到了分辨率为2(?)的高分辨象。结果表明,在β-SiC晶须中普遍存在层错,这些层错存在于(111)面和{111}面上。有些层错终止于晶体内部,形成Burgers矢量b=<111>α/3的Frank不全位错,此外还发现了晶须表面的生长附属物和晶须内的多重孪晶;分析了β-SiC晶须的长大机制。     

电铸铜微观组织与织构的研究

采用扫描电镜、透射电镜和电子背散射衍射技术,研究了不锈钢上厚度约2.2 mm的电铸铜层的微观组织、晶粒取向和晶界特征.实验表明,其组织主要由柱状晶构成,靠近基体50～100 μm处的铸层由细小等轴晶和细小柱状晶构成.对于所有晶区,小角度晶界(<15°)的分布频率较小,大角度(>15°)晶界为电铸铜组织的主要晶界,在大角度晶界中,CSL晶界占有很大比例,其中∑3的分布频率较大.柱状晶由平行分布的层状孪晶构成,近似垂直于柱状晶长轴,层间孪晶界为∑3类型.铸层存在较显著的铜型织构,即<111>择优取向,并且随铸层厚度的增加而加强.     

Lead Zirconate Titanate Thin Films by Aerosol Plasma Deposition: Microstructure Analysis

Lead zirconate titanate (Pb(Zr,Ti)O₃, PZT) thin films were grown on silicon 〈100〉 substrate by aerosol plasma deposition (APD) using solid-state-reacted powder containing donor oxide Nb₂O₅ when keeping the substrate at room temperature and 200°C. Crystalline phases of the deposited films have been analyzed via X-ray diffractometry (XRD), and microstructure via scanning and transmission electron microscopy (SEM and TEM). Cross-sectional TEM revealed that the microstructure comprised several layers including the deposited PZT film and the platinum-electrode-and-titanium-buffered layers on SiO₂–Si substrate. The Pt-electrode layer contained (111)_Pt twinned columnar grains with a slight misorientation and forming low-angle grain boundaries among them. The PZT layer contained randomly oriented grains embedded in an amorphous matrix. Some of the PZT grains, oriented with the zone axis Z = [[Twomacr]11]_PZT parallel to Z = [111]_Pt, were grown epitaxially on the Pt layer by sharing the (111)_PZT plane with the (111)_Pt twinned columnar Pt crystals. However, the existence of such an orientation relationship was confined to several nanosize grains at and near the PZT-Pt interface, and no gross film texture has been developed. An amorphous grain boundary phase, generated by pressure-induced amorphisation (PIA) in the solid state, was identified by high-resolution imaging. Its presence is taken to account for the densification of the PZT thin films via a sintering mechanism involving an amorphous phase on deposition at 25° and 200°C.     

Structural study of β‐SiC(001) films on Si(001) by laser chemical vapor deposition

β‐SiC thin films have been epitaxially grown on Si(001) substrates by laser chemical vapor deposition. The epitaxial relationship was β‐SiC(001){111}//Si(001){111}, and multiple twins {111} planes were identified. The maximum deposition rate was 23.6 μm/h, which is 5‐200 times higher than that of conventional chemical vapor deposition methods. The density of twins increased with increasing β‐SiC thickness. The cross section of the films exhibited a columnar structure, containing twins at {111} planes that were tilted 15.8° to the surface of substrate. The growth mechanism of the films was discussed.     

TEM Characterization of Single- and Multilayer Triol-Based Sol–Gel PZT (53/47) Thin Films

Integrated lead zirconate titanate thin films deposited on Pt/Ti/SiO₂/Si substrates using a novel triol-based route were characterized using X-ray diffraction and transmission electron microscopy. Crack-free single-layer PZT films of up to 200 nm thick were prepared by triol-based sol–gel processing onto Pt/Ti/SiO₂/Si substrates. Films ∼75 nm thick exhibited a microstructure free of pores and second phase. As film thickness increased, film texture changed from {100} to {111} perovskite. Essentially, single-phase multilayer films could be prepared by the deposition and pyrolysis of several 75 nm layers, followed by a single crystallization step. The influence of heat-treatment schedule on the microstructure and orientation of the multilayer films is discussed. Comparison has been made between multilayer films prepared using the triol-based sol and an inverted mixing order/acetic acid-based sol.     

Growth of {111}-oriented diamond on Pt/Ir/Pt substrate deposited on sapphire

Highly 〈111〉-oriented diamond films with azimuthal alignment were successfully deposited on platinum{111}/iridium{111}/platinum{111} formed on sapphire{0001} by microwave enhanced chemical vapor deposition. With oriented nucleation density of approximately 1×10⁸ cm⁻², the heteroepitaxial {111}-oriented diamond films were grown over a 10×10 mm² area without crack or delamination from the substrate. X-Ray diffraction rocking curve of diamond{111} has a full-width at half maximum value of 1.1°, which endorses a high crystal quality of the diamond film. The high density of oriented nucleation and improved adhesion of the diamond can be attributed to the Ir film inserted between the two Pt layers, which hinders diffusion of carbon through the Pt and graphite formation at the Pt/sapphire interface.     

Investigation of heterostructure between diamond and iridium on sapphire

Diamond thin film has outstanding physical and chemical properties. Diamond-on-iridium configurations have been prepared by several methods, such as microwave enhanced plasma CVD, direct currency plasma CVD, and hot filament CVD. In this study, an Ir interlayer was deposited on single crystal sapphires (Al₂O₃) with A-planes {1120} by an RF magnetron sputtering method after annealing samples. In addition, a diamond thin film was deposited by a microwave enhanced plasma chemical vapor deposition (MPCVD) method using a mixture of hydrogen and methane gases after a bias enhanced nucleation (BEN) procedure.Ir (001) was grown on the A-plane of sapphire by X-ray pole figure measurement. Diamond thin films were synthesized on each Ir/sapphire substrate and characterized by SEM, Raman spectroscopy. D {100} faces were exhibited in substantial areas of diamond films, and a flat D {100} plane was partially obtained. It is considered that diamond thin films on Ir {100} were mainly grown towards the <100> direction and were epitaxially grown in part.     

Phase and Texture Evolution in Chemically Derived PZT Thin Films on Pt Substrates

The crystallization of lead zirconate titanate (PZT) thin films was evaluated on two different platinum‐coated Si substrates. One substrate consisted of a Pt coating on a Ti adhesion layer, whereas the other consisted of a Pt coating on a TiO₂ adhesion layer. The Pt deposited on TiO₂ exhibited a higher degree of preferred orientation than the Pt deposited on Ti (as measured by the Full Width at Half Maximum of the 111 peak about the sample normal). PZT thin films with a nominal Zr/Ti ratio of 52/48 were deposited on the substrates using the inverted mixing order (IMO) route. Phase and texture evolution of the thin films were monitored during crystallization using in situ X‐ray diffraction at a synchrotron source. The intensity of the Pt₃Pb phase indicated that deposition on a highly oriented Pt/TiO₂ substrate resulted in less diffusion of Pb into the substrate relative to films deposited on Pt/Ti. There was also no evidence of the pyrochlore phase influencing texture evolution. The results suggest that PZT nucleates directly on Pt, which explains the observation of a more highly oriented 111 texture of PZT on the Pt/TiO₂ substrate than on the Pt/Ti substrate.     

Formation of <111> fiber texture in β-SiC films deposited on Si(100) substrates

The evolution of the morphology and the texture of 3C-SiC films grown by chemical vapor deposition (CVD), using 1,3-disilabutane as precursor, on Si(100) substrates is investigated by transmission electron microscopy. Films were found to exhibit a columnar grain structure with a strong <111> fiber texture and a high density of stacking faults and twins. The columnar grains do not originate at the substrate surface but on a buffer layer about 3 to 5 nm thick, consisting of interconnected 3D-islands that initiate as epitaxial nuclei. The change from <100> epitaxial islands to <111> columnar grains can be understood in terms of anisotropic growth rates and multiple twinning. The observed <111> fiber texture, faulted substructure, faceted surface morphology and carbon enrichment of the growth surface are in agreement with the proposed growth model.     

Tribological behaviour of <100> and <111> fibre textured CVD diamond films under dry planar sliding contact

<100> and <111> fibre textured diamond films are grown on SSiC sliding rings by hot filament CVD and are tribologically tested in dry planar contact under ambient air.The wear of the self-mated textured diamond coating takes place initially at protruding grains of the as-deposited micro rough diamond surface. After 10 km of dry sliding against <100> textured diamond the respective counterparts with <100> and <111> textures exhibit smoothly polished diamond faces without visible surface failures. After dry sliding against <111> textured diamond as static counterpart {100} diamond faces of isolated grains show Hertzian cone cracks and propagation of cracks preferred along {111} easy cleavage planes whereas {111} diamond faces reveal no crack propagation in substrate direction.The results are visualised in a tribo map in which the linear wear of the dynamic diamond face is plotted against the mean coefficient of friction. The best tribological behaviour in terms of low friction and little diamond wear is achieved for sliding couples with <100> fibre texture on the rotating sliding ring and <111> fibre texture on the static ring as mating diamond faces.     

Material characterisation of electroplated nickel structures for microsystem technology

Nickel layers 15 μm thick were pulse plated from a commercially available sulphamate-based electrolyte on an evaporated gold substrate or an electroplated copper substrate. The gold layer showed a (111) crystalline preference orientation, whereas for the copper layer no texture was observed. The deposited nickel layer showed a (110) texture at a low mean current density of 2.5 mA/cm², whereas at a high mean current density of 20 mA/cm² a (100) texture was observed. The structure analysis was supported by SEM pictures of polished and etched cross sections. For the nickel layers deposited on the gold substrate the structure changed from a columnar structure at low mean current densities to a granular structure at high mean current densities, whereas for the layers deposited on copper a granular structure was observed even at low mean current densities.