| 摘要 |
<p>By applying a predetermined process to an element surface of a piezoelectric element which uses a vibration mode in a direction parallel to its direction of polarization, a single crystal element is obtained which can achieve 65% or above for electrochemical coupling coefficient in the vibrating direction which exceeds a value (about 60%) of the conventional tabular piezoelectric element. Specifically, in either one of element surfaces, in a normal direction of which the piezoelectric element is polarized, a plurality of trenches which have a depth extended in a direction essentially perpendicular to the element surface and are filled with an insulating material are formed in a predetermined pitch to form a piezoelectric portion having a comb-like structure and thus a value of 65% or above is achieved in the electromechanical coupling coefficient in a direction parallel to the direction of polarization.</p> |
