Abstract
There are a lot of advantages in microwave heating including energy saving, rapid and selective heating, less pollution, etc. Because of these advantages, microwave heating gradually become a new technique to provide alternative approaches for materials processing. Presently most of applicators for microwave processing of materials are enclosed chambers which have some limitation. To eliminate these limitations, quasi-optical (QO) applicator was designed and applied. Heat treatment of silicon wafers is an important process in the fabrications of MEMS (micro-electro-mechanical-system), solar cells and so on. Otherwise silicon has the strong absorption of microwave energy and low price. Thus silicon wafers are proper to be substrates loaded with materials which have week absorption of microwave. In this thesis, the temperature dependences in silicon and QO applicator were investigated qualitatively during the heating process, including the conductivity, absorbed power of silicon wafers and the variations of the field in QO resonator. Finally as a trial application, negative thermal expansion glass-ceramics was sintered in QO applicator and it was confirmed that the processed negative thermal expansion glass-ceramics has the required crystalline phase of β-spodumene through the XRD (X-ray diffraction) pattern.