講演抄録/キーワード |
講演名 |
2011-10-31 15:40
逆プロトン交換による縦型漏洩弾性表面波の低損失化 ○阿部真也・垣尾省司(山梨大) US2011-64 |
抄録 |
(和) |
縦型漏洩弾性表面波(Longitudinal-type Leaky SAW: LLSAW)は,バルク縦波に近い位相速度を有しており,SAWデバイスの高周波化に有利な伝搬モードの一つであるが,伝搬減衰が非常に大きい.本報告では,LLSAWの伝搬減衰を低減させるため,弾性定数が低減した基板とバルクLN層を組み合わせた基板構造を提案する.LLSAWに対して大きな結合係数K2をもつX-36°Y LiNbO3(LN)に提案構造を適用すると,短絡表面のLLSAW伝搬減衰の計算値は,あるバルク層厚においてゼロ減衰を示した.逆プロトン交換(Reverse Proton Exchange: RPE)法を採用し,X-36°Y LN基板上に提案構造を作製した結果,試料上の一部に,レイリー波のK2が未処理基板の約8割まで回復した領域が存在した.この領域では,未処理試料のLLSAW特性と比較すると,自由表面の伝搬損失が約1/3に減少,挿入損失が大幅に低減,共振特性が格段に向上した. |
(英) |
The longitudinal-type leaky surface acoustic wave (LLSAW) is one of the SAW modes that is advantages for application to high-frequency SAW devices because of its high phase velocity close to that of a longitudinal bulk wave. However, the LLSAW has huge inherent attenuation. In this study, to reduce the attenuation of the LLSAW, we proposed a layered structure of air, a bulk LiNbO3 (LN) layer, and an elastically softened LN substrate. When the layered structure was applied to X-36˚Y LN with a large coupling factor K2 for the LLSAW, zero attenuation for the metallized surface was obtained theoretically at a certain depth of the bulk layer. To realize such a layered structure, a reverse proton exchange (RPE) process was applied to X-36˚Y LN, and the propagation and resonance properties of the LLSAW were evaluated. A good region existed on the RPE wafer, in which the value of K2 for the Rayleigh wave was recovered to approximately 80% of that of the virgin wafer. In comparison with the virgin wafer, the propagation loss for the free surface of the good region on the RPE wafer was decreased threefold, the insertion loss was decreased drastically, and the resonance properties were improved markedly. |
キーワード |
(和) |
縦型漏洩弾性表面波 / 逆プロトン交換 / 伝搬損失 / 共振特性 / / / / |
(英) |
Longitudinal-type leaky SAW / Reverse proton exchange / Propagation loss / Resonance property / / / / |
文献情報 |
信学技報, vol. 111, no. 272, US2011-64, pp. 35-39, 2011年10月. |
資料番号 |
US2011-64 |
発行日 |
2011-10-24 (US) |
ISSN |
Print edition: ISSN 0913-5685 Online edition: ISSN 2432-6380 |
著作権に ついて |
技術研究報告に掲載された論文の著作権は電子情報通信学会に帰属します.(許諾番号:10GA0019/12GB0052/13GB0056/17GB0034/18GB0034) |
PDFダウンロード |
US2011-64 |