UHF Bulk-Acoustic-Wave Filters Utilizing Thin ZnO/SiO2-Diaphragms on Silicon
- 1 March 1986
- journal article
- Published by IOP Publishing in Japanese Journal of Applied Physics
- Vol. 25 (3R) , 371
- https://doi.org/10.1143/jjap.25.371
Abstract
This paper reports on a temperature-stable bulk-acoustic-wave (BAW) filter consisting of a thin ZnO/SiO2 composite diaphragm structure on a silicon wafer. To make a theoretical treatment of the BAW filter possible, the constants for the distributed-parameter equivalent circuit extended to the composite structure are derived from analysis of the dispersion curves for waves propagating along the ZnO/SiO2 diaphragm. Some actual filters are designed and analysed using the equivalent circuit. The measured characteristics of a 578-MHz BAW filter of the two-coupled-resonator type fabricated on silicon are reported and discussed. The results demonstrate that the measured characteristics resemble the theoretical ones but that the insertion loss is as high as 12 dB.Keywords
This publication has 7 references indexed in Scilit:
- ZnO/SiO 2 -diaphragm composite resonator on a silicon waferElectronics Letters, 1981
- Acoustic bulk wave composite resonatorsApplied Physics Letters, 1981
- Fundamental-mode VHF/UHF minature acoustic resonators and filters on siliconApplied Physics Letters, 1980
- Temperature Dependence of the Electroacoustical Constants of Li-Doped ZnO Single CrystalsThe Journal of the Acoustical Society of America, 1969
- A Thin-Film CdS-Quartz Composite ResonatorJournal of Applied Physics, 1967
- A Water-Amine-Complexing Agent System for Etching SiliconJournal of the Electrochemical Society, 1967
- Measurement of Elastic Constants at Low Temperatures by Means of Ultrasonic Waves–Data for Silicon and Germanium Single Crystals, and for Fused SilicaJournal of Applied Physics, 1953