Title :
Unidirectional SAW transducer for GHz frequencies
Author :
Lehtonen, Sake ; Plessky, Victor P. ; Hartmann, Clinton S. ; Salomaa, Martti M.
Author_Institution :
Mater. Phys. Lab., Helsinki Univ. of Technol., Espoo, Finland
Abstract :
A SPUDT structure employing λ/4 and wider electrodes is introduced. The design and its variants exploit the significant difference between the reflectivity of short-circuited λ/4 electrodes and that of floating wide electrodes on 128° LiNbO3. The SAW devices operating at 2.45 GHz have critical dimensions of about 0.4 μm, accessible for standard optical lithography. When matched, the fabricated SPUDT filters exhibit minimum insertion losses of 5.5-7.9 dB together with 3 dB pass-bands of 95-102 MHz.
Keywords :
lithium compounds; photolithography; reflectivity; surface acoustic wave filters; surface acoustic wave transducers; 0.4 micron; 2.45 GHz; 3 dB; 5.5 to 7.9 dB; 95 to 102 MHz; LiNbO3; SAW devices; SPUDT filters; SPUDT structure; electrodes; floating wide electrodes; optical lithography; reflectivity; short circuited λ/4 electrodes; single phase unidirectional transducers; surface acoustic waves; unidirectional SAW transducer; Electrodes; Frequency; Lithography; Matched filters; Optical devices; Optical filters; Reflectivity; Surface acoustic wave devices; Surface acoustic waves; Transducers;
Conference_Titel :
Ultrasonics, 2003 IEEE Symposium on
Print_ISBN :
0-7803-7922-5
DOI :
10.1109/ULTSYM.2003.1293525
