| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a piezoelectric element capable of collectively forming a piezoelectric film including a high dielectric constant part appropriate as an actuator and a low dielectric constant part of which the dielectric constant is lower than that of the high dielectric constant part.SOLUTION: The piezoelectric element comprises the piezoelectric film including a high dielectric constant part 20a in which an a-axis orientation component in a tetragonal component is more than a c-axis orientation component and a low dielectric constant part 20b in which a c-axis orientation component is more than the high dielectric constant part 20a. On an Si substrate 11, the piezoelectric element is formed by: a base structure formation step for forming a base structure 10, on one surface of the Si substrate 11, successively including a stress adjustment layer 12 of which the thermal expansion coefficient is larger than a piezoelectric film 20, and a lower electrode 13; a dielectric film deposition step for depositing a columnar structure film 20 on the base structure 10; a thermal expansion coefficient adjustment step for making the thermal expansion coefficient of the base structure 10 different between the high dielectric constant part 20a and the low dielectric constant part 20b; and a domain structure formation step for heating the piezoelectric film 20 to a 1/4 Curie temperature or higher and 1/2 Curie temperature or lower and then cooling the piezoelectric film to an ambient temperature.SELECTED DRAWING: Figure 1 |
