Piezoelectric element, liquid ejecting head, and liquid ejecting apparatus

A piezoelectric element comprising:

• a first electrode;
• a piezoelectric layer formed above the first electrode to have a longitudinal direction and a transverse direction in a planar view, the piezoelectric layer having a side surface following the longitudinal direction;
• and
• a second electrode formed above the piezoelectric layer,
• wherein at least a part of the side surface of the piezoelectric layer includes a concavo-convex surface having a plurality of concavities and convexities in a cross-sectional view normal to the longitudinal direction, and
• a width of the piezoelectric layer in the transverse direction increases from the second electrode to the first electrode over the extent of the side surface,
• wherein the side surface of the piezoelectric layer has a flat surface connected to an upper surface of the piezoelectric layer,
• the concavo-convex surface is connected to the flat surface,
• the side surface of the flat surface and the second electrode is covered by a first coating layer,
• the concavo-convex surface is covered by a second coating layer, and
• Young's modulus of the second coating layer is smaller than Young's modulus of the first coating layer and Young's modulus of the piezoelectric layer.