| 摘要 |
The present invention provides a piezoelectric device having an extremely good secular characteristic, which is a unimorph (or bimorph) element obtained by sticking to a metal plate a piezoelectric single crystal having a giant-lateral-effect piezoelectric performance of a lateral-vibration-mode electromechanical coupling factor k 31 not smaller than 70%, the unimorph (or bimorph) element having a bending-vibration-mode electromechanical coupling factor k b not smaller than 50 % (or 60 %). A plate-form single crystal 10 of PZNT or PMNT is brought into a mono-domain in its thickness direction and in its plate surface so as to be provided with the giant-lateral-effect piezoelectric characteristic, and the single crystal 10 that does not cause secular deterioration is stuck to a metal plate 20 (shim plate) while the mono-domain quality is kept as it is, as a result of which a unimorph 1 (or bimorph 2) is fabricated. |
