SYNTHESIS OF HEAT RESISTANT, TRANSPARENT POLYARYLATE AND APPLICATION TO WAVEGUIDE TYPE DEVICES

新合成了玻璃化转变温度在200℃以上的耐热聚芳酸酯。研究了一系列聚芳酸酯的光学性质和热稳定性。结果表明，聚芳酸酯具有较高的热稳定性，在可见光和近红外区域具有较高的光学透明性。特别是其中一种聚芳酸酯表现出很高的热稳定性和低的双折射，足以制作光学器件。将电子束光刻技术应用于PAR薄膜，利用电子束直接写入技术和热显影技术在聚芳烃上制作了高分辨率的浮雕光栅。研究还发现，含氟聚芳酸酯对电子束的敏感度比其他聚芳酸酯高20倍。利用具有较高透明度的氟化聚芳酸酯，采用光刻和反应离子刻蚀技术制备了芯尺寸分别为30μm和90μm的多模光波导。由于聚芳酸酯薄膜具有制作光波导所需的优良特性，因此在光电子器件，特别是光互连和光局域网络中具有很好的应用前景。

Heat resistant polyarylates with high glass transition temperature (Tg) over 200℃ were newly synthesized. Optical properties and thermal stability were investigated with a series of polyarylates. It indicated that the Ppolyarylates showed high thermal stability as well as high optical transparency in visible and near IR region. Especially one of polyarylates showed very high thermal stability and low birefringence sufficient for optical device fabrication. EB lithography could be applied to the PAR thin films, and high resolution relief gratings on polyarylate were fabricated by direct electron beam writing technique together with thermal development. It was also found that a fluorinated polyarylate showed higher sensitivity for electron beam by 20 times than other polyarylates. Using the fluorinated polyarylate, which reviels higher transparency, multi-mode waveguides with core sizes of 30μm and 90μm were also fabricated by photoithography and reactive ion etching techniques. From their excellent characteristics sufficient for optical waveguide fabrication, the polyarylate films will be promising candidate for photonic device applications, especially for optical interconnection and for optical local area network.