10 GHz-range surface acoustic wave inter-digital transducers and low loss filters using anodic oxidation technology

The field of mobile communication systems has been developing in recent years, and it is expected that the communication systems will require much higher frequency devices in the future. In order to meet the above requirements, we propose the fabrication of 10 GHz range narrow gap SAW filters using the anodic oxidation technology. It is an advantage of this technology that the operating frequency of Narrow Gap Inter Digital Transducer (NG-IDT) is twice than that of the Conventional Inter Digital Transducer (C-IDT) of the same line width in the lithography pattern. We propose the fabrication of 12 GHz range NG-IDT SAW filter with an electrode width of 0.15 /spl mu/m. The minimum insertion loss is less than 12 dB. We also propose the fabrication of 10 GHz range Narrow Gap Floating Electrode type Uni Directional Transducer (NG-FEUDT) SAW filter, with an electrode width of 0.15 /spl mu/m, using the anodic oxidation technology. Compared with NG-IDT SAW filter, the frequency response of the NG-FEUDT filter has improved because of the reduction of the Triple Transit Echo (TTE). The minimum insertion loss of NG-FEUDT SAW filter is about 10 dB.