Te. Parker et al., 1 F NOISE IN ETCHED GROOVE SURFACE-ACOUSTIC-WAVE (SAW) RESONATORS/, IEEE transactions on ultrasonics, ferroelectrics, and frequency control, 41(6), 1994, pp. 853-862
Measurements of 1/f (or flicker) frequency fluctuations in SAW resonat
ors fabricated with etched groove reflectors on single crystal quartz
have shown that the observed noise levels vary inversely with device s
ize. These measurements were made on sixteen 450 MHz resonators of fou
r different sizes. The 1/f noise levels were also evaluated on twenty-
eight other SAW resonators ranging in frequency from 401 to 915 MHz. T
his additional data provides valuable information on the dependence of
the flicker noise levels on resonator frequency. A model based on loc
alized, independent velocity fluctuations in the quartz is proposed wh
ich correctly fits the observed size and frequency dependence of the m
easured 1/f noise levels. This model suggests that the velocity fluctu
ations originate in small regions (much less than approximately 5 mum
in diameter) randomly distributed throughout the quartz with an averag
e separation of about 5 mum between independent (incoherent) sources.
The magnitude of the localized fractional velocity fluctuation, DELTAu
psilon/upsilon, averaged over a 5 micron cube is on the order of 1 x 1
0(-9).