Micro Fabrication of Aluminum Oxide Patterns Using Local Anodization

摘要

In this study, a novel process for fabricating micro Al2O3 patterns using local anodization is proposed. On the basis of double layer theory, the anodizing region was localized on an aluminum surface near a micro tool electrode with a small inter-electrode gap. The localized oxide formation process was observed by field emission scanning electron microscope (FE-SEM) including energy dispersive spectroscopy (EDS). It was confirmed that micro-scale localized aluminum oxide was fabricated on the aluminum surface. Features of the anodized oxide line were investigated using different ratios of sulfuric and oxalic acid mixtures at various pulse durations and voltage conditions. The experimental results show that an insulating aluminum oxide line pattern was fabricated on 10 mu m aluminum foil. Subsequently, a coplanar waveguide (CPW) micro patch antenna was fabricated and characterized by a PNA network analyzer. The local anodization can be used for fabricating micro-electric circuits without masks and substrate; which will promise the next generation of micro electronic devices.