| 摘要 |
PROBLEM TO BE SOLVED: To secure adhesion of a piezoelectric thin film 4 by reducing peeling stress of the piezoelectric thin film 4 at an end part in a long axis direction, in a structure where an outer shape of a pressure chamber 1a having different cross sectional aspect ratios includes a curve part 12.SOLUTION: A piezoelectric diaphragm 10 includes a substrate 1 with a pressure chamber 1a formed thereon, and a piezoelectric thin film 4 which is arranged on the substrate 1 and is partially positioned above the pressure chamber 1a. Aspect ratios of cross sections of the pressure chamber 1a are different from each other. At least a part of an outer shape of the cross section of the pressure chamber 1a includes a curve part 12 projected to the outside of the pressure chamber 1a. At least a part of the piezoelectric thin film 4 is formed along the curve part 12 of the pressure chamber 1a, above the pressure chamber 1a. When a distance between a sidewall 1b of the pressure chamber 1a and the piezoelectric thin film 4 in an X axis direction as a long axis direction of the cross section of the pressure chamber 1a is dμm, and a distance between the sidewall 1b of the pressure chamber 1a and the piezoelectric thin film 4 in a Y axis direction as a short axis direction is dμm, d>dis satisfied. |
