New Piezoelectric Thin Film Resonator Promising for Use in Very High Frequency Communication Systems

新型压电薄膜谐振器有望用于甚高频通信系统

基本信息

批准号：
11305025
负责人：
NAKAMURA Kiyoshi
金额：
$ 18.24万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A).
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11305025/
关键词：
Piezoelectric Resonator Acoustic Multilayers ZnO LiTaO_3 Crytal MBE Thin Film Resonator ZnO薄膜

项目摘要

The purpose of this study is to investigate a new piezoelectric thin film resonator using acoustic λ/4 multilayers, which is promising for use in a very high frequency range from 1 to 20GHz and can be incorporated within integrated circuits. The main results of this study are summarized below.1. The λ/2 mode configuration of piezoelectric thin film resonator using acoustic λ/4 multilayers, where the piezoelectric film is λ/2 thick, was analyzed in consideration of propagation loss, and then electrical quality factor Q and effective electromechanical coupling factor K were calculated as functions of the acoustic impedance ratio of multilayers and the layer number.2. The quality of c-axis oriented piezoelectric ZnO films grown by ECR-assisted MBE were evaluated with RHEED and X-ray diffraction. It has been confirmed that high quality ZnO single crystal films can be grown.3. A new simple evaluation method for acoustic properties, such as density and stiffness, of thin films was proposed. In this method, the acoustic properties are evaluated from the measured resonance frequency change of high overtones of a piezoelectric thickness-mode resonator due to deposition of a test film on the resonator surface.4. Dispersion characteristics of elastic waves which propagate along the surface being trapped in a piezoelectric film were analyzed. It has been shown that a vibration trapped in the finite electroded region can be occurred.5. A 3-GHz piezoelectric ZnO film resonator with five λ/4 acoustic multilayers was fabricated on a Z-cut LiTaO_3 substrate and this type of resonators were shown to be promising for use in a very high frequency range from 1 to 20GHz.

本研究的目的是研究一种使用声波 λ/4 多层膜的新型压电薄膜谐振器，该谐振器有望在 1 至 20GHz 的极高频率范围内使用，并可集成到集成电路中，概述如下：1。考虑到传播，分析了使用声学 λ/4 多层的压电薄膜谐振器的 λ/2 模式配置，其中压电薄膜的厚度为 λ/2损耗，然后计算电品质因数Q和有效机电耦合因数K作为多层膜声阻抗比和层数的函数。2．评价了ECR辅助MBE生长的c轴取向压电ZnO薄膜的质量。通过RHEED和X射线衍射证实可以生长出高质量的ZnO单晶薄膜。 3．提出了一种简单的In声学性能评价方法。该方法通过测量压电厚度模式谐振器由于在谐振器表面沉积测试薄膜而产生的高泛音谐振频率的变化来评估声学特性。 4．对压电薄膜中的振动进行了分析，结果表明，可以在有限电极区域内发生振动。 5．该谐振器在 Z 切 LiTaO_3 基板上制造，并且这种类型的谐振器被证明有望在 1 至 20GHz 的极高频率范围内使用。