Accession Number : AD0824083

Title :   VHF FILTER CRYSTAL RESEARCH.

Descriptive Note : Quarterly rept. no. 2, 16 Apr-15 Jul 67,

Corporate Author : CLEVITE CORP CLEVELAND OH ELECTRONIC RESEARCH DIV

Personal Author(s) : Koneval, D. J. ; Roberts, D. A. ; Leo, H. ; Sliker, T. R.

Report Date : NOV 1967

Pagination or Media Count : 33

Abstract : The Q sub m of a 100 MHz 5th harmonic mode resonator was determined as dielectric tuning was used to lower the resonant frequency of the unit a total of 2,278 kHz (2.3%). Initially, the tuning layer of silicon monoxide had little or no effect on resonator Q sub m; however, as the frequency was continually decreased in 100 kHz increments, the Q sub m began to decrease until with 2.3% lowering it was approximately one half the initial value. A further decrease in Q sub m was observed as the crystal with 2.3% lowering was exposed to the atmosphere. Initial data indicate the additional decrease can be attributed to the absorption of moisture by the tuning layer. An attempt to fabricate 100 MHz and 150 MHz inverted mesa resonators with an electrode diameter to wafer thickness ratio of 30 was unsuccessful. Minor fabrication problems were responsible. Fabrication was started on the contract sample group of 100 MHz 5th harmonic mode inverted mesa resonators having an electrode diameter to wafer thickness ratio of 25. Included in the group for comparison are several conventional resonators having the same electrode configuration. The frequency-temperature dependence of several rotated cut CdS single crystals has been determined. In the region of interest for quasi-pure thickness shear mode operation a variation of -54.5 ppm/C was observed. A theoretical calculation was also made to determine the temperature coefficients required of the individual components to realize a zero first order temperature coefficient for the CdS-quartz composite resonator device. (Author)

Descriptors :   (*QUARTZ RESONATORS, TUNING DEVICES), (*PIEZOELECTRIC CRYSTALS, RESONATORS), (*FILMS, RESONATORS), (*DIELECTRICS, TUNING DEVICES), CADMIUM SULFIDES, SINGLE CRYSTALS, HARMONIC ANALYSIS, FREQUENCY, RESPONSE, RESONANT FREQUENCY, SILICON COMPOUNDS, OXIDES, VERY HIGH FREQUENCY, CRYSTAL FILTERS.

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE