RESEARCH INTO NEW APPROACHES FOR VHF FILTER CRYSTALS.
Abstract
Trapped-energy mode theory predicts the existence of inharmonic overtone modes whose resonant frequencies are dependent both on electrode dimensions and on the difference in resonant frequency between the electroded and surrounding regions of an AT-cut quartz wafer. Trapped energy mode theory also predicts that these modes can have observable responses only when mode resonance occurs below the wafer cut-off frequency. Both predictions have been confirmed for measurements on wafers with rectangular electrodes aligned in the Z' direction. Initial measurements on multielectroded resonators indicate that individual dot-resonators can be electrically connected in parallel to form on one wafer in effect a single large resonator with a strong clean response. Experiments with AT-cut mesa resonators indicate that higer values of mechanical modes can be obtained with larger resonant frequency differences between the mesa region and the surrounding regions of the wafer. However, satisfactory methods for fabricating mesa resonators have not yet been developed. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 26, 1963
- Accession Number
- AD0430492
Entities
People
- D. J. Koneval
- Damian Curran