Title :
Highly oriented ta2o5 piezoelectric thin films prepared by rf-magnetron sputtering
Author :
Kakio, Shoji ; Mitsui, Takeshi ; Tsuchiya, Akinori ; Nakagawa, Yasuhiko
Author_Institution :
Interdiscipl. Grad. Sch. of Med. & Eng., Univ. of Yamanashi, Kofu, Japan
Abstract :
Highly X-axis-oriented tantalum pentoxide (Ta2O5) piezoelectric thin films were deposited on a SiO2 substrate using an RF-magnetron sputtering system with a metal tantalum target and an O2-radical source. The degree of orientation and the Rayleigh-type surface acoustic wave properties were evaluated. When the SiO2 substrate temperature was 700°C and the O2 flow rate was 10 ccm, the coupling factor K2 of the oriented Ta2O5 thin film with a normalized thickness h/¿ of 0.21 was measured to be 0.88% and was about 3/4 of that for the previously obtained thin film using a DC-diode sputtering system. In the deposition on Si(100), a higher orientation was observed. Moreover, for the 1st mode of the Rayleigh-type SAW on the Ta2O5/MgO(100), the K2 of 1.42% and the phase velocity of 5,126 m/s were obtained for the normalized thickness h/¿ of 0.225.
Keywords :
piezoelectric thin films; sputter deposition; surface acoustic waves; tantalum compounds; MgO; O2-radical source; RF-magnetron sputtering; Rayleigh-type surface acoustic wave properties; SiO2; Ta2O5; coupling factor; film deposition; highly oriented piezoelectric thin films; metal tantalum target; orientation degree; phase velocity; temperature 700 degC; Acoustic waves; Cathodes; Film bulk acoustic resonators; Piezoelectric films; Semiconductor thin films; Sputtering; Substrates; Surface acoustic waves; Temperature; Thin film devices; RF-magnetron sputtering; X-axis-oriented tantalum pentoxide thin film; piezoelectric thin film;
Conference_Titel :
Ultrasonics Symposium (IUS), 2009 IEEE International
Conference_Location :
Rome
Print_ISBN :
978-1-4244-4389-5
Electronic_ISBN :
1948-5719
DOI :
10.1109/ULTSYM.2009.5441475
