| MEMS(Microelectronic Mechanical System) has been applied in more and more fields with the development of the science and technology. But as one of the packaging technology, anodic bonding is the key technology of MEMS. This kind of technology has some advantages, such as simply technics, higher bonding strength, the good capability of airproof. Following the requirement of high bonding strength, bonding materials also should be suited. Compared with traditional glass, glass-ceramic have many advantages,such as high mechanics strength and rigidity. It has good chemistry and heat stability, so it can be used in many bad environment. It also has good performances in insulated. Compared with traditional glass, glass-ceramics has higher mechanical strength and could be bonded to silicon at lower temperature.In this dissertation, Li2O-Al2O3-ZnO-SiO2(LAZS)and Li2O-Al2O3-SiO2(LAS) system glass-ceramics, which replace the tradition hot-resistant glass, were chose to as anodic bonding materials which were matched to metal(stainless steel) and silicon for MEMS. The basic glasses were prepared by adopting conventional melt quenching technology and the temperature of nucleation and crystallization were determined by using DTA. The suitable composition and heat-treatment of glass-ceramic, which can be bonded with stainless steel and silicon, be found. The thermal expansion coefficient of glass-ceramics were matched to the bonding material by choosing the proper composition and controlling the heat-treatment of glass-ceramics, in order to reduce the residual stress on the interfacial, lower the temperature of bonding, improve the quality of bonding. Anodic bonding between stainless steel or silicon and glass-ceramics were realized. At the same time we studied the rule about the parameter of low temperature bonding and capability of bonding, analysed the microstructure of the bonding interfacial and discussed the anodic bonding mechanism between glass-ceramics and metal(stainless steel) or silicon. Then the factors of voltage, temperature and time of bonding which could influence the result of anodic bonding were researched. This study is great significant for enlarging the area which anodic bonding can be used, pioneering the new application about the glass-ceramic.The main achievement of this dissertation are briefly mentioned as follows:(1) Development of MEMS was summarized. The bonding technologies and the developing tendency of anodic bonding technology were presented. Glass-ceramics used as packaging materials and anodic bonding materials were analyzed. The studying work purpose and signification of the dissertation were briefly introduced.(2) Li2O-Al2O3-ZnO-SiO2 (LAZS) glass-ceramics were obtained after tow-step heat-treatment. The coefficient of thermal expansion(CTE), the main properties of the glass-ceramics, can be adjusted by controlling the size and density of the crystals. The crystalline phases of the glass-ceramic were investigated by means of the XRD. The results show that most of the main crystal phase of the samples is Li2SiO3. But the main crystal phase will change with the change of the content of alkali metals. The bending strength of this glass-ceramics is measured by bending strength test instrument and it also high enough to meet the requirement as anodic bonding with stainless steel. Following the increasing of temperature, the coefficient of thermal expendation was increased. The tiptop of it was 131.6×10-7/℃-142.32×10-7/℃and the most bending strength was 95.91MPa.(3) Li2O-Al2O3-SiO2 (LAS) system glass-ceramics were used to anodic bonding with silicon were fully discussded. The crystallization mechanism of LAS glass had been analyzed by DTA(Differential Thermal Analysis) and XRD(X-ray Diffraction). The kinetic parameters such as crystallization active energy were calculated by Kissinger, JMA equation and modified JMA equation, to analyzed the influence of the ratio of Li and Al on LAS glass crystallization kinetics. The analysis of crystal phase composition and microstructure of glass-ceramics were made by means of XRD, SEM. The relation between constituents, microstructure and properties of glass-ceramics was researched. The influence of the chemical composition of glass-ceramics and nucleation agents on the crystal phase, microstructure and the thermal expansion coefficients was studied. The results indicated: the main crystal phase of the glass-ceramics wasβ-Spodumene orβ-quartz solid solutions, the coefficients of thermal expansion (CTE) were (20.20-31.11)×10-7/℃, with which could be matched well with silicon.(4) Some typical LAS glass-ceramics were prepared by two-step heat-treatment method, and the electrical properties of glass-ceramics used as anodic bonding material were briefly researched. The effect of heat-treatment schedule on performance of CTE, mechanical strength, resistivity and dielectric constant had been studied. The effect of technical parameter of voltage, temperature and time on bonding performance was discussed. to reduce the bonding voltage and dielectric loss of Micro-electronic devices, the electrical properties of glass-ceramics were studied, and results show that the resistivity of glass-ceramics was higher than matrix glass, the dielectric constant and dielectric loss of glass-ceramics were lower.(5) The materials were surfaced by abrasive and polishing equipment. Their surface finish quality was tested by SEM, AFM. The surface techniques of deionized water, chemical polishing and plasma etching were adopted. The influence of the surface techniques on the bonding quality was contrasted. The various factors affecting of anodic bonding were analyzed. Based upon this, the various testing methods of bonding intensity were appraised. The approach of low temperature bonding has been proposed,and the model of anodic bonding of silicon/glass-ceramic was established by analyzing the microstructure of bonding surface and interface.(6) The experimental of anodic bonding of stainless steel/glass-ceramics and silicon/glass-ceramics was made for the first time. At the same time we studied the rule about the parameter of low temperature bonding and capability of bonding, analysed the microstructure of the bonding interfacial and discussed the anodic bonding mechanism between glass-ceramics and metal(stainless steel) or silicon. Then the factors of voltage, temperature and time of bonding which could influence the result of anodic bonding were researched.(7) The facility of anodic bonding was made by ourselves (air environment), and another one was purchased(vacuum environment). At the same time, the super optical microscope of depth of field and the polishing facility were set up. The study on glass-ceramics of low-temperature anodic bonding for application in MEMS is complicated, because it involves science of glass, crystallography, physics, chemistry, fine processed technology and testing technology, which is a very hard work. But its application is very wide. This investigate is great significant for enlarging the new application field which anodic bonding and the glass-ceramics, and the research is not perfect and must be improved.The project was supported by the National Natural Science Foundation of China (50472039) and the Hubei Provincial Natural Science Foundation of China (2005ABA011).
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