Evaluation of resonators fabricated from high quality quartz

A set of evaluation tests of resonators fabricated from quartz grown from several different types of cultured nutrients in both commercial- and research-size autoclaves is reported. The aluminum content was determined by three different physical techniques: electron paramagnetic resonance, low-temperature IR absorption measurements on swept material, and acoustic loss measurements on sodium-swept resonator blanks. Low-temperature IR measurements were also used to monitor the as-grown OH bands (OH growth-defects). The room temperature mechanical Q was measured on 5-MHz fifth-overtone AT-cut resonator blanks. Acoustic loss versus temperature spectra were taken on unswept, air- or hydrogen-swept, and Na-swept blanks, and the relation between the defect-related loss and the growth conditions was characterized. Room temperature irradiation had no effect on the acoustic loss spectra