论文部分内容阅读
本文叙述声表面波器件用的薄膜材料、薄膜多层结构中的声表面波传输特性计算以及薄膜声表面波视中频滤波器。由于溅射电极结构的改良,确立了具有均匀的膜厚、结晶性和相当于单晶的85-88%的机电耦合系统的ZnO压电膜的大量生产的技术基础。另外还研完了r-Bi_2O_3族化合物(Bi_(12)GeO_(20),Bi_(12)TiO_(20)等)的薄膜化,成功地合成了新材料Bi_(12)PbO_(19)压电膜。对ZnO-SiO_2-Si多层结构的声表面波传输特性(速度温度变化率,耦合系数等)进行了数据分析,确定了具有大于单晶ZnO的辆合系数以及相速度和群速的零温度变化率的结构(膜厚及晶轴方向等)。用玻璃基片上的ZnO压电膜试制了彩色电视用的视中频滤波器,其性能为中心频率57兆赫,插入损耗13分贝(调谐时),插入损耗20分贝(电阻终端),衰减极点的温度特性15×10~(-6)/℃。
This paper describes the thin film materials used in SAW devices, the calculation of SAW transmission characteristics in thin-film multi-layer structures, and the thin film SAW IF filter. Due to the improvement of the structure of the sputtering electrode, the technical basis for mass production of a ZnO piezoelectric film having a uniform film thickness, crystallinity and an electromechanical coupling system corresponding to 85-88% of a single crystal was established. In addition, a new thin film of Bi_ (12) PbO_ (19) piezoelectric film was successfully prepared by thinning of r_ Bi_2O_3 compounds such as Bi_ (12) GeO_ (20) and Bi_ (12) TiO_ (20) . The surface acoustic wave propagation characteristics (rate of temperature and temperature change, coupling coefficient and so on) of ZnO-SiO_2-Si multi-layer structure were analyzed. It was found that the vanishing coefficient and the zero temperature of phase velocity and group velocity Structure of rate of change (film thickness and crystal axis direction, etc.). Using a ZnO piezoelectric film on a glass substrate, a video-on-demand filter for color television was tested with a center frequency of 57 MHz, an insertion loss of 13 dB (at tuning), an insertion loss of 20 dB (resistance termination) Features 15 × 10 -6 / ℃.