Quartz Crystal Radiation Effects

The effects of electron irradiation on frequency and on internal friction, Q-1, of 5 MHz, 5th overtone, high precision AT-cut quartz resonators are evaluated. The oscillators were irradiated with 10 MeV electrons to a dose of 1 Mrad(Si), transient and permanent frequency shifts monitored, and resonator internal friction measured before and after irradiation in the temperature range of 4.2 to 475°K. This investigation was carried out under nearly identical manufacturing and experimental conditions on resonators fabricated from natural, electronic grade synthetic, lithium carbonate doped, lithium nitrite doped, low impurity content high-Q, and electrolyzed (swept) electronic grade synthetic quartz crystals. The swept synthetic crystal oscillator shows the highest radiation tolerance.