| 摘要 |
<p>A stress relaxing layer L22 composed of MgO is formed on the upper surface of a substrate layer L1 in order to alleviate stress acting on a piezoelectric layer L3, the stress relaxing layer L22 is removed while leaving behind a region D1 where the piezoelectric layer L3 is to be formed, and the single crystal piezoelectric layer L3 is formed on the upper surface of the stress relaxing layer L22. As a result, the stress relaxing layer L22 in a region D2 where the piezoelectric layer L3 is not to be formed is preliminarily removed, the region D1 where the piezoelectric layer L3 is to be formed is reduced in size, and stress acting on the piezoelectric layer L3 attributable to the difference in lattice constant between the stress relaxing layer L22 and the piezoelectric layer L3 and thermal expansion is alleviated, thereby enabling favorable single crystallization of the piezoelectric layer L3.</p> |
