磷矿伴生硅资源制备单质硅的探讨

综述了国内外以四氟化硅、氟硅酸钠（钾）、无定SiO2为硅源制备单质硅的主要方法,并对以无定SiO2为硅源制备单质硅的工艺条件进行了研究与探索。     

Verfahren zur Herstellung von Solarsilicium

Production of solar silicon. Economic exploitation of solar energy using solar cells made of crystalline silicon is dependent upon a considerable drop in the cost of the silicon raw material which is nowadays produced by standard methods of the semiconductor industry. New procedures for producing less expensive solar silicon can be divided into four groups characterized by different physico-chemical purification techniques: (1) reduction of volatile Si-H-Cl compounds; (2) purification of technical grade silicon (98–99%); (3) reduction of hexafluorosilicates; (4) reduction of silicon dioxide. Among the ten solar silicon processes under discussion, the purification of technical grade silicon and the carbothermal reduction of silicon dioxide have the greatest scope for cost reduction; however, it remains to be established whether the necessary purity can be achieved on an industrial scale.     

碳化硅材料中游离硅及游离碳对性能的影响

研究了全碳粉反应渗硅碳化硅（PCRBSC）材料的结构与力学性能的关系。分析了渗硅碳化硅材料中游离硅（fsi),游离碳（fc)含量对抗折强度的影响。结果表明：参硅碳化硅材料中随游离硅（fsi)含量的增加,其抗折强度下降,并且二者呈直线关系,符合线性复合规划,另一方面,游离碳（fc)含量较高的渗硅碳化硅材料,尽管游离硅（fsi)含量低,但其抗折强度低于等量或较多游离硅（fsi)含量的渗硅碳化硅材料的抗折强度。     

超细SiO2表面改性及在孔结构材料合成中的应用

从回收利用二氧化硅废料颗粒的角度出发,用硅烷类偶联剂对废料颗粒进行表面改性,并将其作为合成有序硅基孔结构材料的原料。傅里叶红外光谱、热重分析、激光光散射结果表明达到了改性目的。然后用TEM和SEM研究了晶化温度对硅基孔材料形态的影响,发现优化合成条件可以得到有序结构材料,为超细二氧化硅废料的回收利用提供了可能。     

多晶硅生产中硅芯氧化问题探究

改良西门子法生产多晶硅中硅芯是多晶硅生长的载体,硅芯氧化会降低多晶硅产品品质,硅芯氧化的产品对下游铸锭、直拉均有不同程度的影响。目前硅芯氧化是影响多晶硅产品质量的一大问题。分析了硅芯氧化机理,针对相关因素开展了试验,提出了降低硅芯氧化率的措施。     

Effect of crystal plane orientation on the friction-induced nanofabrication on monocrystalline silicon

Although monocrystalline silicon reveals strong anisotropic properties on various crystal planes, the friction-induced nanofabrication can be successfully realized on Si(100), Si(110), and Si(111) surfaces. Under the same loading condition, the friction-induced hillock produced on Si(100) surface is the highest, while that produced on Si(111) surface is the lowest. The formation mechanism of hillocks on various silicon crystal planes can be ascribed to the structural deformation of crystal matrix during nanoscratching. The silicon crystal plane with lower elastic modulus can lead to larger pressed volume during sliding, facilitating more deformation in silicon matrix and higher hillock. Meanwhile, the structures of Si-Si bonds on various silicon crystal planes show a strong effect on the hillock formation. High density of dangling bonds can cause much instability of silicon surface during tip disturbing, which results in the formation of more amorphous silicon and high hillock during the friction process. The results will shed new light on nanofabrication of monocrystalline silicon.     

On the Growth and Microstructure of Carbon Nanotubes Grown by Thermal Chemical Vapor Deposition

Carbon nanotubes (CNTs) were deposited on various substrates namely untreated silicon and quartz, Fe-deposited silicon and quartz, HF-treated silicon, silicon nitride-deposited silicon, copper foil, and stainless steel mesh using thermal chemical vapor deposition technique. The optimum parameters for the growth and the microstructure of the synthesized CNTs on these substrates are described. The results show that the growth of CNTs is strongly influenced by the substrate used. Vertically aligned multi-walled CNTs were found on quartz, Fe-deposited silicon and quartz, untreated silicon, and on silicon nitride-deposited silicon substrates. On the other hand, spaghetti-type growth was observed on stainless steel mesh, and no CNT growth was observed on HF-treated silicon and copper. Silicon nitride-deposited silicon substrate proved to be a promising substrate for long vertically aligned CNTs of length 110–130 μm. We present a possible growth mechanism for vertically aligned and spaghetti-type growth of CNTs based on these results.     

Growth of Alumina/Metal Composites into Porous Ceramics by the Oxidation of Aluminum

Alumina/metal composites were grown into the pores of porous alumina, porous aluminosilicate, and porous silicon carbide substrates through the oxidation of Al–Si (5 wt%) powder compacts coated with magnesia powder (11 mg/ cm²). The thickness of the resulting composite increased with oxidation time and temperature, and was proportional to (pore size)^0.5 on using porous alumina. The composite thickness was more than 2 times larger in the silicon carbide and about 4 times larger in the aluminosilicate than in the alumina at 1523 K for 1 h. The products using these three types of substrates consisted of alumina, aluminum, and silicon, except that a silicon carbide phase occurred when using the silicon carbide substrate. Silica and mullite in the aluminosilicate substrate changed to silicon and alumina, and silica in the silicon carbide substrate changed to silicon because of the reduction by aluminum.     

硅切割废砂浆制备粗孔块状硅胶的工艺研究

提出了以硅切割废砂浆中的硅粉为硅源,制备粗孔块状硅胶,同时回收硅切割废砂浆中的碳化硅磨料和聚乙二醇切削液的工艺。重点阐述了基本原理和工艺流程,并对工艺条件进行了优化。水解反应工艺条件：硅、碳化硅混合颗粒和氢氧化钠的质量比为3.38∶1,在80 ℃下反应85 min,然后将温度提高到95 ℃继续反应150 min,最终的硅粉水解率达到100%。多硅酸钠制备硅胶工艺条件：凝胶反应在pH=10、温度为40 ℃条件下进行,硅凝胶在45 ℃老化10 h,并用质量分数为0.04%的稀氨水扩容,可得到比表面积为405 m²/g、孔容为1.422 6 mL/g的粗孔块状硅胶。该工艺实现了硅切割废砂浆回收联产粗孔块状硅胶,使硅切割废砂浆的回收更加经济合理。     

Nitridation of Silica Characterized by High-Energy X-Ray Diffraction Technique

The structure of amorphous silicon oxynitride formed under nitridation conditions using ammonia gas, before the onset of silicon nitride crystallization, is determined employing high-energy X-ray diffraction (HEXRD) technique. The derived real-space function suggests that smaller ring structures, especially 3R and 4R (R: ring), which are the dominant rings in crystalline silicon nitride, are not major species in amorphous silicon oxynitride, and form in the latter part of the silicon nitride crystallization.     

Porous silicon nanocrystals in a silica aerogel matrix

ABSTRACT: Silicon nanoparticles of three types (oxide-terminated silicon nanospheres, micron-sized hydrogen-terminated porous silicon grains and micron-size oxide-terminated porous silicon grains) were incorporated into silica aerogels at the gel preparation stage. Samples with a wide range of concentrations were prepared, resulting in aerogels that were translucent (but weakly coloured) through to completely opaque for visible light over sample thicknesses of several millimetres. The photoluminescence of these composite materials and of silica aerogel without silicon inclusions was studied in vacuum and in the presence of molecular oxygen in order to determine whether there is any evidence for non-radiative energy transfer from the silicon triplet exciton state to molecular oxygen adsorbed at the silicon surface. No sensitivity to oxygen was observed from the nanoparticles which had partially H-terminated surfaces before incorporation and so we conclude that the silicon surface has become substantially oxidised. Finally, the FTIR and Raman scattering spectra of the composites were studied in order to establish the presence of crystalline silicon; by taking the ratio of intensities of the silicon and aerogel Raman bands, we were able to obtain a quantitative measure of the silicon nanoparticle concentration independent of the degree of optical attenuation.     

碳化硅在聚合物中的应用

综述了碳化硅（SiC）在用填充改性、表面包覆改性、离子注入改性和聚合物表面接枝改性等方法所制得的复合材料中的应用，并对纳米SiC改性环氧树脂、纳米微晶SiC改性聚乙烯基咔唑和香豆素共混物、聚吡咯包覆改性SC、硅离子注入改性聚对苯二甲酸乙二醇酯薄膜及丙烯酰胺接枝改性SiC等进行了详细讨论     

渗硅碳化硅材料结构与性能关系的研究

采用低廉石油焦碳分为原料制造全碳粉生坯，通过有机添加剂来调配生坯中碳的比例，以控制烧结体中游离硅（fsi）、游离碳（fC）含量（其中fs,fc为烧结中未反应的硅和碳），研究了全碳粉反应硅碳化硅（PCRSC）材料的结构与力学性能的关系，分析了渗硅碳化硅材料中游离硅、游了碳含量对抗弯强度的影响。结果表明：渗硅碳化硅材料中随游离硅含量的增加，其抗弯速度下降，并且二者呈直线关系，符合线性复合规则，另一方面，游离碳含量较高的渗硅碳化硅材料，尽管游离硅含量低，但其抗弯强度低于等量或较多游了硅含量的渗硅碳化硅材料的抗弯强度。     

硅溶胶—苯丙乳液复合路标涂料的研制

采用正硅酸乙酯(TEOS)为主要原料,以聚合溶胶法制备硅溶胶,制得的硅溶胶与苯丙乳液冷拼复配得到复合基料,再以该基料制得硅溶胶—苯丙复合路标涂料。通过正交试验分别确定了制备硅溶胶、硅溶胶—苯丙复合乳液和硅溶胶—苯丙复合路标涂料的最优方案。     

Effect of some technological parameters on structure formation in materials based on reaction-sintered silicon carbide

Results of petrographic, x-ray, chemical, and spectral investigations of the structure and composition of materials based on SiC fabricated by reaction sintering of preforms pressed from grainy silicon carbide and its mixtures with petroleum coke in molten and volatilized silicon are presented. It is shown that the structure and composition of reaction-sintered silicon carbide materials can be controlled by changing the proportion of silicon carbide and petroleum coke in the pressed preform, the coarseness of carbide and carbon particles, the density of the pressings, and the temperature of reaction sintering. It is established experimentally that secondary silicon carbide formed as a result of the reaction between petroleum coke and silicon binds the grains of the initial carbide into a dense silicon carbide skeleton, whereas the retained pores are filled with free silicon. A single-phase material consisting entirely of silicon carbide can hardly be obtained by the method of reaction sintering. In practice, this method gives double-phase (SiC-Si) and triple-phase (SiC-Si-C) materials with a maximum content of the principal phase (SiC) equal to 94–96% (mass fractions).Translated from Ogneupory i Tekhnicheskaya Keramika, No. 8, pp. 2–8, August, 1996.     

云南省水稻增施硅肥肥效及优化施肥量研究

通过全省近１０ａ（１９８８ ～１９９９）硅肥在水稻上施用的结果及土壤化验资料分析,研究了土壤有效硅、硅肥用量与硅肥肥效的相关性,提出了水稻增施硅肥的土壤硅素的丰缺指标及优化施肥量。     

反应烧结碳化硅的显微组织及其导电性的研究

研究了液态硅参与下的反应烧结碳化硅的工艺参数、显微组织对其电阻率的影响.随着烧结气氛压力和成型压力增加,反应烧结碳化硅中游离硅量减少,电阻率增加.其烧结机理以碳的溶解及碳化硅的淀析过程为主.     

Conductive poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) polymer glue as an ohmic and rectifying electrical contact for H‐terminated n‐Si and p‐Si wafers

An organic conductive glue based on a blend of poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and d ‐sorbitol was examined for laminating conductors to crystalline silicon. The PEDOT:PSS glue functions as a high‐work‐function solution processable conductor and exhibits an ohmic contact on p‐type silicon and a rectifying contact on n‐type silicon. Under illumination, the n‐Si/PEDOT:PSS:d ‐sorbitol junctions exhibit current–voltage characteristics suggesting minority carrier trap states, leading to charge recombination at the silicon/polymer interface. Conductive glue for laminating to crystalline silicon is desirable for making electrical contacts to flexible materials such as molecular semiconductors, graphene or transparent conductive oxides. These materials could eliminate the need for metal contacts to the front face of silicon solar cells. Conductive glue could prove especially useful for laminating to textured silicon or novel micro‐ or nanostructured silicon materials. © 2018 Society of Chemical Industry     

Chemical and structural transformations of silicon submitted to H2 or H2/CH4 microwave plasmas

Silicon substrates are often used to synthesize polycrystalline diamond films by microwave plasma assisted chemical vapour deposition technique (MPCVD). In the case of highly oriented diamond films, several steps are employed to carefully prepare the silicon surface (pre-treatment steps), to nucleate diamond crystals (nucleation step) and to thick the film (growth step). In this study, we characterize {100} silicon substrates and diamond released from its silicon substrate by electronic microscopies (TEM and SEM), by Atomic Force Microscopy (AFM) and by X-ray photoelectron spectroscopy (XPS), to follow the substrate transformations after each step, particularly the formation and the evolution of the silicon carbide and to characterise the diamond films grown on the carburised silicon. We show that according to the experimental conditions and the level of surface/gas contamination by carbon and silicon species, isolated islands or continuous β-SiC compound are formed over the silicon surface and can generate defects such as voids or strip structures that influence the subsequent diamond nucleation and growth.     

Making reusable reaction-bonded silicon nitride crucibles for silicon casting from kerf-loss silicon waste

Silicon kerf loss during wafer slicing and the broken quartz crucibles after silicon casting are two major solid wastes from photovoltaic (PV) industry. Especially, the recycle of kerf-loss silicon has become an urgent issue because near 100 000 t of solid wastes are generated every year. One of the most meaningful recycle routes of the kerf-loss silicon is to make silicon nitride crucibles to replace the quartz crucibles. In this study, we demonstrated how this is feasible through acid leaching refining, slip casting, and nitridation. The reaction-bonded silicon nitride (RBSN) crucibles after oxidation were found pure enough for silicon ingot growth. More importantly, they could be reused after ingot growth. With the present examples, the potential of using the kerf-loss silicon for fine ceramics is prominent.