On the Fabrication and Performance of SAW Delay Line Filters for GHz SAW Oscillators

A 2-GHz SAW delay line (DL) oscillator is realized without external filtering and matching networks by using the third harmonic passband of 0.58μm linewidth SAW double interdigital transducers (4F-IDTs). The simple design technique of SAW DL filters for GHz SAW DL harmonic oscillators is briefly discussed, based on the state of the art of submicrometer pattern formation techniques. The theoretical considerations and experiments on submicrometer linewidth IDT pattern formation by conventional contact printing are also described. 0.58μm linewidth 4F-IDTs on rotated Y-cut quartz, which consist of 622 lines and a O.4-mm aperture, have been successfully realized by contact printing without using the lift-off process, The frequency response of the SAW DL harmonic filter and the performance of the 2-GHz device are presented and critically discussed.