TY - JOUR
T1 - Small surface acoustic wave duplexer for wide-band code-division multiple access full-band system having good temperature characteristics
AU - Kadota, Michio
AU - Nakao, Takeshi
AU - Nishiyama, Kenji
AU - Kido, Shunsuke
AU - Kato, Masanori
AU - Omote, Ryoichi
AU - Yonekura, Hiroshi
AU - Takada, Norihiko
AU - Kita, Ryoichi
PY - 2007/7/26
Y1 - 2007/7/26
N2 - A small surface acoustic wave (SAW) duplexer for a wide-band code-division multiple access (W-CDMA) system with a good temperature coefficient of frequency (TCF) has been required. However, the conventional SAW duplexer for W-CDMA using Al electrode/50-70° YX-LiNbO3 is large (3.8 x 3.8 mm 2) and its TCF is not good (-80ppm/°C). When a SiO2 film is deposited on this substrate to improve its TCF, good frequency characteristics cannot be realized. Thus, by using a new structure such as a flattened SiO2 film/Cu electrode/substrate structure to improve the TCF, YX-LiNbO3 substrate to obtain a large coupling factor, and flip-chip bonding to miniaturize the duplexer, a small (3 x 2.5 mm2) SAW duplexer having a low insertion loss and a good TCF has been realized for the first time.
AB - A small surface acoustic wave (SAW) duplexer for a wide-band code-division multiple access (W-CDMA) system with a good temperature coefficient of frequency (TCF) has been required. However, the conventional SAW duplexer for W-CDMA using Al electrode/50-70° YX-LiNbO3 is large (3.8 x 3.8 mm 2) and its TCF is not good (-80ppm/°C). When a SiO2 film is deposited on this substrate to improve its TCF, good frequency characteristics cannot be realized. Thus, by using a new structure such as a flattened SiO2 film/Cu electrode/substrate structure to improve the TCF, YX-LiNbO3 substrate to obtain a large coupling factor, and flip-chip bonding to miniaturize the duplexer, a small (3 x 2.5 mm2) SAW duplexer having a low insertion loss and a good TCF has been realized for the first time.
KW - Duplexer
KW - Excellent TCF
KW - Love wave
KW - W-CDMA
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U2 - 10.1143/JJAP.46.4714
DO - 10.1143/JJAP.46.4714
M3 - Article
AN - SCOPUS:34547903920
VL - 46
SP - 4714
EP - 4717
JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
SN - 0021-4922
IS - 7 B
ER -