METHOD OF MANUFACTURING FOR PIEZOELECTRIC DEVICES Russian patent published in 2008 - IPC H03H3/04 H03H3/10 

FIELD: radio.

SUBSTANCE: method of manufacturing for piezoelectric device includes fabricating of piezoelectric unit with mounted in holder piezoelectric element with subsequent hardening and encapsulation. Hardening is carried out in cycles. In each cycle piezoelectric unit frequency is measured in normal conditions at fixed temperature, volume with piezoelectric unit placed in it is vacuumed up to pressure of about 1·10^-2...1-10^-3 mmhg, vacuumed volume is heated up to temperature of 110±10°C, holded at this temperature for 120 h, then the temperature is lowed and the pressure is raised in vacuumed volume, then piezoelectric device frequency is measured and the change of piezoelectric unit frequency in one hardening cycle is determined at the same fixed temperature of normal conditions. Hardening cycles are repeated until frequency change for last hardening cycle would be equal to set value of frequency fluctuation for service life. Time period of piezoelectric unit being out of vacuumed volume should not exceed 6-8 h. The invention will increase long-term stability of piezoelectric device frequency for more than by order.

EFFECT: increasing of long-term stability of piezoelectric device frequency.