TY - GEN
T1 - RF filter using boundary acoustic wave
AU - Kando, Hajime
AU - Yamamoto, Daisuke
AU - Mimura, Masakazu
AU - Oda, Tetsuya
AU - Shimizu, Atushi
AU - Shimoda, Kazunori
AU - Takata, Eiichi
AU - Fuyutsume, Toshiyuki
AU - Kubo, Ryuichi
AU - Kadota, Michio
PY - 2006/12/1
Y1 - 2006/12/1
N2 - Authors report a new structure of a shear horizontal (SH) type boundary acoustic wave for cellular phone applications. Such a structure composed of electrodes with a low shear wave velocity between two materials, namely, the SiO2 film/high density electrode/LiNbO3 substrate, is proposed. The unique feature of this structure is that it does not require a cavity on the substrate surface. The ladder filter and the longitudinal coupled multiple mode filter composed of this structure is reported. By changing the propagation angle of the acoustic wave, the electromechanical coupling factor k2 ranged from 0 to 16% as well as a normalized bandwidth of 0.67 to 1.85 fold as large as that of a 36-46° Y-X LiTaO3 leaky surface acoustic wave (LT-LSAW) filter. In addition, an excellent temperature coefficient of delay time (TCD=25 ppm/°C) and a large mutual coupling coefficient κ12 (=0.15) were also obtained. The newly developed RF filter using this structure was very small and thin.
AB - Authors report a new structure of a shear horizontal (SH) type boundary acoustic wave for cellular phone applications. Such a structure composed of electrodes with a low shear wave velocity between two materials, namely, the SiO2 film/high density electrode/LiNbO3 substrate, is proposed. The unique feature of this structure is that it does not require a cavity on the substrate surface. The ladder filter and the longitudinal coupled multiple mode filter composed of this structure is reported. By changing the propagation angle of the acoustic wave, the electromechanical coupling factor k2 ranged from 0 to 16% as well as a normalized bandwidth of 0.67 to 1.85 fold as large as that of a 36-46° Y-X LiTaO3 leaky surface acoustic wave (LT-LSAW) filter. In addition, an excellent temperature coefficient of delay time (TCD=25 ppm/°C) and a large mutual coupling coefficient κ12 (=0.15) were also obtained. The newly developed RF filter using this structure was very small and thin.
KW - Boundary acoustic wave
KW - Electromechanical coupling factor adjustment
KW - Power flow angle
KW - RF filter
KW - SH wave
UR - http://www.scopus.com/inward/record.url?scp=47249150212&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=47249150212&partnerID=8YFLogxK
U2 - 10.1109/ULTSYM.2006.59
DO - 10.1109/ULTSYM.2006.59
M3 - Conference contribution
AN - SCOPUS:47249150212
SN - 1424402018
SN - 9781424402014
T3 - Proceedings - IEEE Ultrasonics Symposium
SP - 188
EP - 191
BT - 2006 IEEE International Ultrasonics Symposium, IUS
T2 - 2006 IEEE International Ultrasonics Symposium, IUS
Y2 - 3 October 2006 through 6 October 2006
ER -