Submicron fabrication technology using electro-chemical effects and application to GHz-range unidirectional SAW transducers

The frequency ranges of mobile communication systems are now in GHz and is extending to 2/spl sim/4 GHz. Moreover SAW devices require the frequency range of around 10 GHz. The submicron technology below 0.1 /spl mu/m is required. In this paper, we propose a new lithography technique that can make below 0.05 /spl mu/m electrode width. The electrodes are fabricated by using very thin anodic oxidation films as resists and wet or dry etching techniques. Also, new lithography technologies using electro-chemical effects are described in the fabrication process of the unidirectional SAW IDT with a different thickness and a material electrode using a single photolithography method. The results show the 0.075 /spl mu/m width IDT with thickness about 0.03 /spl mu/m on 128/spl deg/ Y-X LiNbO/sub 3/. SAW experimental results show 17 GHz and 10 GHz-range SAW conventional interdigital transducers filters and the 1 GHz low loss filters with the insertion loss around 5 dB.<
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