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In recent years, with the development of science and technology, micro-electromechanical systems in more and more areas of the wide range of applications. But as a key technology for microelectromechanical systems package - the semiconductor silicon and glass anodic bonding together technology, there are still many problems. At home and abroad using anodic bonding of Pyrex and SD-2 glass as the silicon substrate package material. These two types of glass not only has a lower etch rate, and the temperature dependence of the thermal expansion coefficient and the wafer do not quite match, resulting encapsulated residual stress is large, difficult to bring to the packaging process. Compared with the two types of glass, glass-ceramic with high mechanical strength, hardness and wear resistance; good chemical and thermal stability; excellent electrical insulation properties, dielectric loss, dielectric constant and stable advantages. Therefore, this subject with the crystallized glass in place of the conventional glass, in order to achieve good bonding of the microcrystalline glass and silicon wafers at a lower temperature (<350 ° C). 2 O-Al 2 O 3 -SiO 2 (LAS) glass as the topics chosen Li The material of the substrate together with the anodic bonding of silicon wafers adapted. The system base glass obtained using conventional melt cooling method, using differential thermal analysis (DTA) to determine the Nucleation and crystallization temperature of the base glass, and then a different heat treatment system on the base glass to heat treatment. By X-ray diffraction (XRD), scanning electron microscopy (SEM) analysis of the main phase of the glass types, size, content and microstructure morphology analysis of heat treatment on the glass and thermal properties, mechanical properties, resistance rate and dielectric properties. At a temperature of 200 to 400 ° C, under the conditions of voltage of 400 to 600V, microcrystalline glass and silicon anodic bonding experiment to study the influence of process parameters such as voltage, temperature, time of anodic bonding performance. Bonded microscopic surface and interface analysis, to further explore the mechanism of the glass-ceramic and silicon anodic bonding. Obtained the following findings: 1, with the increase in the time of nucleation and crystallization, glass main crystalline phase are β-spodumene constant, thermal expansion coefficient, flexural strength first increases and then decreases small, resistivity increases, the dielectric constant and dielectric loss showed a decreasing trend. 2, when the heat treatment system for 670 ℃ / 3h, 80 ℃ / 3h, the coefficient of thermal expansion of the glass is 31.16 × 10 -7 / ℃ (200 ~ 400 ℃), flexural strength 186.64MPa, resistivity of 1.02 × 10 12 (?) · m (20 ° C), the dielectric constant of 21.5 (20 ° C), fit with the silicon anodic bonding together. 3, the bonding strength with the increase in voltage, temperature increases, the voltage, temperature, impact the performance of the bonding of the larger, less impact on bonding performance. When the voltage is 500V, the temperature is below 200 ° C can not be realized when the bond. When the voltage is 500V, the temperature was 400 ° C, bond strength 10.25 MPa. In this study, funded by the National Natural Science Foundation of China (50472039) and the Natural Science Foundation of Hubei Province (2005ABA011).
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