Silic-like Micro-structures Fabricated by X-ray Irradiation of Polymethylislesquioxane Spin-on Glass Films

摘要

A process fabricate 100 m high aspect ratio micro-optical sturctures by direct X-ray exposure and development of polymethylsilsesquioxane spin-on glass (GR 650 using polymethylomethacrylate (PMMA) molds patterned by deep X-ray lithography (DXRL). The process presented in this article utilizes GR 650 as a DXRl resist. The polymethylsilsesquioxane is converted to silica on the surface exposed to air, and cross linked throughout the bulk. X-ray irradianted regions are then selectively retained by development in an organic solvent. A technique to cast 100 m thick GR 650 films was established. Although the height of the structures fabricated was 100 m, this technique can be extended to larger structural heights. An alternative positive tone proces swas also developed in which the irradiated regions of GR 650 films are etched in buffered HF. The structural height achieved by positive tone procesisng. however, was limited to 15 mum, which is the depth of conversion to silica. Surface and bulk compositions of the irradiated films were measured by XPS and Fourer Transform infrared spectroscopy.