In this paper we report the results of a radiation testing program on swept-synthetic quartz resonators and materials. Thirteen resonators representing eight bars of Z-growth, swept-synthetic quartz were tested for transient frequency drifts and accumulated frequency offset. When the drift due to the temperature change induced by a radiation pulse equilibrates, a relatively permanent frequency offset which changes with dose is observed. Typical frequency changes are found to be approximately +2 pp 108 for doses of a few kilorads to about 5 x 104 rads and -1 pp 107 after 2 x 105 rads. Crystals cut from the same bar exhibit frequency shifts which differ by about 1 pp 108 for a given dose, but crystals from different bars differ by larger amounts for a given dose. Changes observed in a resonator irradiated in a mixed gamma-neutron environment to 175 kilorads and 3 x 1014 n/cm2 cannot be accounted for by ionization-induced changes alone. Positive frequency shifts, linear in neutron fluence, are observed. Electron spin resonance and transient and steady-state optical absorption measurements were performed on pieces of the parent material in an attempt to correlate the observed frequency changes with defect properties. Two radiation-induced electron spin resonance centers wereob-served, one of which appears to anneal at the same temperature as the frequency shift due to ionizing radiation. Predictions of frequency shifts with accuracies of approximately 1 pp 107 can be made from measurements of a piece of a bar. More accurate predictions require the testing of a finished oscillator from each bar. Copyright © 1969 by The Institute of Electrical and Electronics Engineers, Inc.
