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In this paper, two aspects in the wet glass etching, the pre-annealing of the glass and the mask process, are taken into consideration to achieve the deep and defect-free wet etching of Pyrex glass. Compared with the conventional strategies, i.e.,HFsolution component and mask kinds, our experiment results prove the pre-annealing is another key role to obtain theoretical isotropy character in wet etching. Besides, the high temperature pre-annealing dramatically improves the structure profiles and reduces the notching defects. Additionally, a novel multilayer mask process is proposed. With 1.5μmPR/ 100nmAu/ 100 nmAu/ 20 nmCrmask and > 450 °C pre-annealing, > 150 μm deep and non-pin-holes Pyrex glass structures are achieved and the roughness of etched surface is lower than 1 nm.

Nanogetters, based on carbon nanotubes (CNTs) coated Ti films, do have higher pumping speed and possibly larger sorbed quantity compared with traditional getters, such as St175 of SAES [1]. Although the nanogetter is with the outstanding performance, it is still hard to be integrated into micro electro mechanical systems (MEMS) packaging and devices due to high growth temperature of CNTs (>700°C) [2], poor adhesion with substrate [3, 4], vulnerability to pollute the wafers and difficulty to pattern. Therefore, this paper proposes a promotion of nanogetter based on transferring out vertically aligned CNTs (VA-CNTs) utilizing the glass frit. Compared with the conventional nanogetters, the promotion processes have advantages of (1) compatibility to the MEMS materials with controllable melting temperature and coefficient of thermal expansion (CTE), (2) Enhancement of the adhesion between CNTs and substrate, (3) Avoiding polluting the package wafer during CNTs growth. The results indicate that the promotion processes can be fulfilled by the silicon wafers and have wide applications such as nanogetters, field emission display, etc.

This paper presents an analysis about the variation of quality factor (Q-factor) aiming at the complex micro resonator to explore the mechanism of the energy loss under different pressures. To demonstrate the work, a series of resonators are designed, which mainly differs in the squeeze-damping and scale of the beam. According to corresponding structure, the Q-factor is measured at different pressures while the theoretical air damping model combined with Christians model is also proposed. The air damping models of three types are proved to have 10%~30% relative error compared to experimental results in low vacuum, respectively. And, for the high vacuum, the structural energy loss plays an important role on the Q-factor, which increases with the decrement of comb quantity and the beam width.

Radio Frequency Identification (RFID) tag is one of the Automatic Identification technology, its application has been involved in all aspects of daily life. A new micro manufacturing technology called Aerosol Jet® printing is described to fabricate the RFID tag in this paper. The fabrication method of Aerosol Jet printing RFID tag is that print the line using sliver ink as the seed first, and then electroplate copper to increase the line width and thickness to reduce the resistance, thus it would get the higher quality factor Q. The width of seed lines printed is 60 μm with the tip of 250 μm in diameter. The inductance value of RFID tag printed is in the range of 2.87 μH to 2.97 μH, it meets the required value of 2 μH to 6 μH.

Ultra-light calcium silicate material constructed with fibrous xonotlite crystals has an advantage of low-thermal conduction coefficient. But the microporous structure can hardly make a better performance in terms of super thermal insulation. Although nanoporous structure of SiO2-aerogel satisfies the requirement, its tenacity is not strong enough to produce by itself blocky super thermal insulation material. This research, thus proposes to apply SiO2-aerogel as nanoporous carrier in the process of preparation, with Ultra-light calcium silicate material constructed with fibrous xonotlite crystals as the matrix so as to prepare nanoporous super thermal insulation material compounded with Xonotlite-SiO2-aerogel via so-gel method and ethanol supercritical drying. SEM and pore size distribution techniques were here applied to characterize the morphology and pore structure of the composite material. The results show that the SiO2-aerogels were better distributed in pore of calcium silicate matrix, with the pore size distribution of composite ranging from 10 nanometers to 50 nanometers, and average pore size less then 20 nm.

Spherical alumina powder and dispersant were mixed with distilled and deionized water, and ball milled to make alumina slurry. The slurry was dried in a high magnetic field to make a compact. Subsequently, the compact was cold-isostatic-pressed (CIP) to enhance the homogeneity in particle packing density. Anisotropy of shrinkage during sintering was examined for the alumina compacts in detail. Particle orientation existed in the spherical alumina powder compacts prepared in 10T, and made them shrink anisotropically during sintering. Sintering shrinkage was larger in the direction parallel to magnetic field direction (i.e., the c-axis direction of alumina crystal) than that in its perpendicular direction. The particle orientation structure in the compacts was confirmed with the immersion liquid method of polarized light microscope, and the grain alignment structure in the sintered bodies was also observed with X-ray diffraction, the c-plane was perpendicular to the magnetic field direction. On the other hand, isotropic sintering shrinkage occurred in the spherical alumina powder compacts prepared in 0T, which did not hold the particle orientation. The experimental results indicate that sintering shrinkage of spherical alumina powder compact depends on alumina crystal axis direction. Origin of the sintering shrinkage anisotropy for the spherical alumina powder compacts can be attributed to the particle orientation caused by high magnetic field.

Neural network (NN) is an effective method in the filed of materials design, but the convergent speed is decided by initial weights. This paper proposes genetic neural network algorithm (GNNA) to design materials. Aluminum titanate modification is studied by the method of GNNA. The results indicate the algorithm works well.

Carbide slag was used as raw materials for the first time to prepare xonontlite whiskers via a hydrothermal route without special instruments and synthesis conditions. And the effect of pH value of emulsion of carbide slag and hydrothermal conditions on removal rate of impurities, morphology and crystallinity of synthesized xonotlite whiskers were explored using ICP, SEM and XRD techniques. The results indicated that the carbide slag after purification could be used to prepare xonotlite whiskers, and different pH values of emulsion of carbide slag had great impact on the removal rate of impurities and morphology of xonotlite whiskers. Xonotlite whiskers with 20-40 μm in length and 100-500 nm in diameter were hydrothermally synthesized at 230 °C for 15 h with using silicic acid as kiesel material.

Mullite fiber porous ceramic was prepared by forced liquid displacement forming and using Mullite precursor sols as binders. SEM studies have shown that the uniformity of integral ceramic is good although the binder and fiber congregate slightly. Mullite precursor sols spread to films or congregate together in miniature. The mullite sol binders between fibers limit to the contact points and the redundant binders form flat film even if they are superfluous, and the pores were not built up even where the binders congregate badly. The results from mercury porosimetry testing of the mullite fiber porous ceramic showed the relationship of cumulative intrusion and diameter for mullite fiber porous ceramic using colloidal mullite binder, and the mean pore size is 45.6μm. The pore size distribution is very broad, from about 0.2 to 174.9μm.

The calcined carbide slag was used to prepare xonotlite by replacing quicklime as the calcareous materials. Effects of calcination temperature on the mineral composition of the carbide slag, lime activity and synthesized xonotlite were studied. The results indicated that carbide slag after proper calcination can be used to prepare xonotlite. Calcination temperature has no effect on the synthesized xonotlite, but has a great impact on lime activity and morphology of secondary particles of xonotlite.

The K2SO4-Na2SO4 system was studied by differential scanning calorimetry (DSC) with the aim of developing a new phase-change thermal energy storage material. The temperature range of phase change is from 800°C to 1069°C according to the phase diagram. A new shape-stabilized phase-change material made of molten salts impregnated by capillary forces in a porous-fiber matrix was presented. These materials were characterized by X-ray diffraction analysis and differential scanning calorimetry analysis. The results indicated that the compound included 70~80% of molten salts, meanwhile the heat storage material could keep its shape without any leakage during the heating process.

A new control method of the particle orientation structure with super high magnetic field is studied for Al2O3 ceramics. Al2O3 slurry was made with two types of Al2O3 particles, which one was spherical shape of, and the other one was elongated shape of. The Al2O3 ceramics of orientation structure was fabricated by drying the Al2O3 slurry under the super high magnetic field, cold isostatic pressing (CIP) and sintering. Effects of particle shape, particle size, the solid loading, slurry viscosity, dispersant content and the magnetic field strength on the particle orientation structure were examined in detail. The experimental results indicate that even the spherical Al2O3 particles can align under the magnetic field; the particle orientation degree changes with the particle shape and the solid loading under same magnetic field strength conditions, and the elongated particle system is easier to align than the spherical particle system; the particle orientation degree of the Al2O3 ceramics can be controlled by adjusting the particle shape, particle size, solid loading, slurry viscosity, dispersant content and magnetic field strength.

In this paper, microspheres were prepared by using Chinese bauxite as raw materials through centrifugal spray drying method. The microstructure and composition of ceramic microsphere were investigated by X-ray diffraction, scanning electron microscope and X-ray energy spectrum. The particle size was 10~100#m. The XRD analysis reveals that the main crystalline phase of the ceramic microsphere were α-Al2O3 and mullite (3Al2O3•2SiO2). The Al2O3 content (chemical composition) of the microspheres was little more than 70%, and the molar ratio of Al2O3/SiO2 was near to the molar ratio of alumina and silica of mullite.

The photocatalyst of nanometer ZnO powder was prepared by precipitation method with ZnSO4⋅7H2O and Na2CO3 as raw materials. Laboratory experiments with methyl orange (MO) as the model pollutant have been carried out to evaluate the photocatalytic activity of nanometer ZnO photocatalyst. A high-pressure mercury lamp was used as the energy source for the photocatalytic experiments. The effects of process parameters such as catalyst loading, initial methyl orange concentration, pH and electrolyte on the photodegradation have been investigated.

Nanometer cobalt oxide powders were obtained by decomposition of precursors CoC2O4×2H2O at 350°C for 3h. The precursors were synthesized by solid-state reaction with H2C2O4×2H2O and CoCO3 under microwave irradiation. The products were characterized by XRD and TEM. The results showed that the nanometer Co3O4 is cubic and the mean particle is 19 nm with narrow distribution and weak agglomeration.