Piezoelectric element and method for manufacturing piezoelectric element

A method for manufacturing a piezoelectric element, the method comprising:

• a first electrode formation step of forming a first electrode on a silicon substrate;
• a first piezoelectric film formation step of forming a first piezoelectric film on the first electrode;
• a second electrode formation step of forming a second electrode on the first piezoelectric film;
• an adhesion layer formation step of forming an adhesion layer on the second electrode;
• an interlayer formation step of forming an interlayer on the adhesion layer the interlayer being formed of a material different from that of the second electrode and having a thickness of 0.4 μm to 10 μm;
• a third electrode formation step of forming a third electrode on the interlayer;
• a second piezoelectric film formation step of forming a second piezoelectric film on the third electrode;
• a fourth electrode formation step of forming a fourth electrode on the second piezoelectric film;
• and
• a removal step of removing a part of the silicon substrate by etching,
• wherein each of the first electrode, the first piezoelectric film, the second electrode, the interlayer, the adhesion layer, the third electrode, the second piezoelectric film, and the fourth electrode is formed using a thin film formation method.