广东省化纤行业的现状及未来发展建议

通过对广东省化纤发展现状和有利因素进行分析,指出了主要存在问题,提出未来发展建议.     

Synthesis of acicular α-Bi2O3 microcrystals by microwave-assisted hydrothermal method

ABSTRACT

Materials based on bismuth(III) oxide are candidate to be used in optical and electronic devices because of their properties such as a variable band gap, photoconductivity, photoluminescence, high refractive index, and dielectric permittivity. These properties are dependent of several factors, e.g., present phases and crystal morphology. The microwave-assisted hydrothermal method (MAH) is a fast and efficient approach of synthesis to obtain semiconductor powders. However, the synthesis of monoclinic bismuth oxide (α-Bi₂O₃) with acicular morphology by MAH was not found in literature. In this paper, microcrystals of acicular α-Bi₂O₃ (monophasic) were successfully obtained by MAH using a synthesis temperature of 80°C for 0.5?h. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron, and transmission electron microscopies showed the formation of a monoclinic structure (space group P21/c) with acicular morphology that grew along the [001] direction. The temperature and time necessary to synthetize acicular microcrystals were significantly lower than those found for acicular microcrystals obtained by conventional hydrothermal method.     

氧化芋头淀粉理化性质研究

以芋头淀粉为原料、过氧化氢为氧化剂,在碱性介质中制备了低氧化度芋头淀粉。经扫描电镜分析,氧化芋头淀粉颗粒呈多角状,平均颗粒直径18.09μm。X-射线衍射确定其晶体形貌为A型结构。流变学分析其糊化温度为79.5℃、特性粘度为2.505 Pa.s,粘弹性曲线显示其粘性大于弹性。其塑性测定结果符合Croass模型,稠度指数为85.56 s。     

Ultralow Dielectric Constant Tetravinyltetramethylcyclotetrasiloxane Films Deposited by Initiated Chemical Vapor Deposition (iCVD)

Simultaneous improvement of mechanical properties and lowering of the dielectric constant occur when films grown from the cyclic monomer tetravinyltetramethylcyclotetrasiloxane (V4D4) via initiated chemical vapor deposition (iCVD) are thermally cured in air. Clear signatures from silsesquioxane cage structures in the annealed films appear in the Fourier transform IR (1140 cm^?1) and Raman (1117 cm^?1) spectra. The iCVD method consumes an order of magnitude lower power density than the traditional plasma‐enhanced CVD, thus preserving the precursor's delicate ring structure and organic substituents in the as‐deposited films. The high degree of structural retention in the as‐deposited film allows for the beneficial formation of intrinsically porous silsesquioxane cages upon annealing in air. Complete oxidation of the silicon creates ‘Q’ groups, which impart greater hardness and modulus to the films by increasing the average connectivity number of the film matrix beyond the percolation of rigidity. The removal of labile hydrocarbon moieties allows for the oxidation of the as‐deposited film while simultaneously inducing porosity. This combination of events avoids the typical trade‐off between improved mechanical properties and higher dielectric constants. Films annealed at 410 °C have a dielectric constant of 2.15, and a hardness and modulus of 0.78 and 5.4 GPa, respectively. The solvent‐less and low‐energy nature of iCVD make it attractive from an environmental safety and health perspective.     

Synchronous Growth of High‐Quality Bilayer Bernal Graphene: From Hexagonal Single‐Crystal Domains to Wafer‐Scale Homogeneous Films

The precise control of the domain structure, layer thickness, and stacking order of graphene has attracted intense interest because of its great potential for nanoelectronics applications. Much effort has been devoted to synthesize semiconducting Bernal (AB)‐stacked bilayer graphene because of its tunable band structure and electronic properties that are unavailable to single‐layer graphene. However, fast growth of large‐scale bilayer graphene sheets with a high AB‐stacking ratio and high mobility on copper poses a tremendous challenge, which has to overcome the self‐limiting effect. This study reports a low‐cost but facile method to rapidly synthesize bilayer Bernal graphene by atmospheric pressure chemical vapor deposition using polystyrene as the feedstock. The bilayer graphene grains and continuous film obtained are of high quality and exhibit field‐effect hole mobilities as high as 5700 and 2200 cm² V^?1 s^?1 at room temperature, respectively. In addition, a synchronous growth mechanism of bilayer graphene is revealed by monitoring the growth process, resulting in a high surface coverage of nearly 100% for a near‐perfect AB‐stacking order. This new synthesis route is significant for industrial application of bilayer graphene and investigation of the growth mechanism of graphene by the chemical vapor deposition process.     

电子显微镜技术表征树脂中橡胶相的显微结构形态

本文采用染色和化学刻蚀技术,通过透射电子显微镜(TEM)和扫描电子显微镜(SEM)对ABS树脂、高抗冲聚苯乙烯(HIPS)树脂、乙丙共聚聚丙烯SPl79、AWl91树脂中橡胶相的显微结构形态进行表征.结果表明,当树脂中橡胶相含双键时,采用硫化染色和四氧化锇(OsO4)染色技术,均能观察到树脂中橡胶相的显微结构形态,且采...     

清洗液温度及浓度对硅研磨片清洗效果的影响

超声波清洗在硅片生产中具有广泛的应用,影响超声波清洗效果的因素有很多,如清洗液温度、清洗液浓度等。为了研究清洗温度和清洗液浓度对硅研磨片清洗效果的影响,在实验中通过改变清洗液温度及清洗液的浓度,最后观察硅片表面洁净情况。得出清洗液温度和清洗液浓度不是越高越好,在某一具体工艺下,都存在一个适宜范围,在适宜范围内,硅片的清...     

一种新型超净高纯试剂在半导体技术中的应用

通过对新型超净高纯试剂同常规CMOS酸碱试剂同时进行CMOS工艺中栅氧化前的清洗实验,从清洗后硅片残留金属量的电感耦合高频等离子体原子发射光谱分析、硅片表面形貌的AFM分析和MOS电容测量三个方面进行了应用实验.结果表明,以超净高纯乙腈为主要组分的新型试剂,其清洗效果总体优于常规CMOS酸碱试剂,可以考虑在半导体器件相应清洗工艺中采用.