Applications of SAW resonators in high-performance instrumentation

Abstract

The role that SAW (surface-acoustic-wave) resonators have come to play in high-performance test instrumentation is reviewed. The contributions made by SAW resonators in a number of Hewlett-Packard (HP) instrument applications are detailed. SAW-controlled oscillators are now the preferred design for precision frequency-control applications in the frequency range 200 MHz-1 GHz. The challenges in device design, fabrication, packaging and testing for these demanding applications are discussed.

Novel Surface Transverse Wave Resonators with Low Loss and High Q

“…The IDT's are unapodized and located synchronously with the mirror gratings. Metal electrodes consist of 4 % copper doped aluminum evaporated by resistance heating [12].…”

“…This is in part because of the added requirement of waveguiding structures for STW.In spite of this, some potential advantages of STW resonators have been long been recognized or conjectured, including: decreased surface sensitivity and superior aging behavior; increased power handling ability, due to deeper penetration into the bulk; 60 % higher frequency operation than SAW resonators with the same feature size on 0090-5607/87/0000-0319 $1 .OO 0 1937 IEEE wafers worth of STW resonators at 500 MHz, 632MHz, and 1726 MHz. Fabrication and packaging processes closely follow what we have described elsewhere for SAW resonators[12,17].…”

Applications of surface acoustic and shallow bulk acoustic wave devices

“…SAW resonators employing reflection gratings [123], [124] are employed for precision filtering and oscillator applications. H igh-Q SAW-resonator oscillators are now the preferred design for precision frequency-control application in the frequency range 200 MHz to 1 GHz, involving spectrum analyzers, frequency synthesizers, as well as carriernoise test sets [125], [126]. Noise floors of -176 dBc/Hz have been reported for precision SAW-resonator oscillators [127].…”

“…Photograph of a 3 x 5-mm four-cavity SAW resonator chip ribbon-bonded to ceramic base. (Reprinted with permission from Bray, see [125].) mercial5 mm x 3 mm four-cavity SAW-resonator filter, chipribbon bonded to a ceramic base.…”

“…mercial5 mm x 3 mm four-cavity SAW-resonator filter, chipribbon bonded to a ceramic base. Substrates are O.5-mm thick, 50-mm diameter, 3B.4° V-rotated quartz with SAW propagation along the X-axis, chosen to give zero TCO at 35°C [125].…”