TY - GEN
T1 - FBAR using LiNbO3 thin film deposited by CVD
AU - Kadota, Michio
AU - Suzuki, Yusuke
AU - Ito, Yoshihiro
PY - 2010/12/1
Y1 - 2010/12/1
N2 - The authors have realized a film bulk acoustic wave resonator (FBAR) usinga thin LiNbO3 film deposited by a chemical vapor deposition (CVD) forthe first time. As a result, a 2.9GHz FBAR, which is higher than 2.1GHz of theBAW using a LiNbO3 single crystal thin plate, with an impedance ratioof 40dB at a resonant (fr) and an antiresonant (fa) frequencies was realized.The LiNbO3 film has a mixture of the polarity. As a result of ascanning non-linear dielectric microscope (SNDM) measurement, c domains and cdomains occupy 82% and 18%, respectively. A quality factor is small because itis considered that the film has the mixed polarity, the thickness is not flatand the structure of electrode is not optimum. A transverse mode was not excitedon the fabricated FABR. According to a calculation, the transverse wave mode isobserved when the thickness of electrodes is thin. On the other hand, thetransverse wave mode isn't observed when the thickness of electrodes is thick.The main responses of longitudinal mode wave are not different by thethicknesses of electrodes. Therefore it is found that the transverse wave modecan be suppressed by selecting the thickness of electrodes. Further, the effectthat LiNbO3 film is twinned crystalline epitaxial one is evaluated bycalculation. The transverse wave mode is excited even if the film is twinnedepitaxial one. It is important to deposit another oriented LiNbO 3film with larger coupling factor to realize a wider band resonator.
AB - The authors have realized a film bulk acoustic wave resonator (FBAR) usinga thin LiNbO3 film deposited by a chemical vapor deposition (CVD) forthe first time. As a result, a 2.9GHz FBAR, which is higher than 2.1GHz of theBAW using a LiNbO3 single crystal thin plate, with an impedance ratioof 40dB at a resonant (fr) and an antiresonant (fa) frequencies was realized.The LiNbO3 film has a mixture of the polarity. As a result of ascanning non-linear dielectric microscope (SNDM) measurement, c domains and cdomains occupy 82% and 18%, respectively. A quality factor is small because itis considered that the film has the mixed polarity, the thickness is not flatand the structure of electrode is not optimum. A transverse mode was not excitedon the fabricated FABR. According to a calculation, the transverse wave mode isobserved when the thickness of electrodes is thin. On the other hand, thetransverse wave mode isn't observed when the thickness of electrodes is thick.The main responses of longitudinal mode wave are not different by thethicknesses of electrodes. Therefore it is found that the transverse wave modecan be suppressed by selecting the thickness of electrodes. Further, the effectthat LiNbO3 film is twinned crystalline epitaxial one is evaluated bycalculation. The transverse wave mode is excited even if the film is twinnedepitaxial one. It is important to deposit another oriented LiNbO 3film with larger coupling factor to realize a wider band resonator.
KW - CVD
KW - FBAR
KW - LiNbO film
KW - Resonator
KW - transverse mode
KW - twinned crystallineepitaxial film
UR - http://www.scopus.com/inward/record.url?scp=80054061323&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80054061323&partnerID=8YFLogxK
U2 - 10.1109/ULTSYM.2010.5935491
DO - 10.1109/ULTSYM.2010.5935491
M3 - Conference contribution
AN - SCOPUS:80054061323
SN - 9781457703829
T3 - Proceedings - IEEE Ultrasonics Symposium
SP - 91
EP - 94
BT - 2010 IEEE International Ultrasonics Symposium, IUS 2010
T2 - 2010 IEEE International Ultrasonics Symposium, IUS 2010
Y2 - 11 October 2010 through 14 October 2010
ER -