Piezoelectric device, liquid discharging head, and liquid discharging apparatus

A piezoelectric device comprising:

• a pressure chamber having a sidewall;
• a piezoelectric element having a substantially rectangular-shaped outer edge and a substantially rectangular-shaped inner edge, the inner edge forming a hollow center;
• and
• a diaphragm disposed between the pressure chamber and the piezoelectric element,
• wherein:
• the pressure chamber is formed by the sidewall and the diaphragm,
• the diaphragm has a crystal plane {100} of a single crystal silicon base,
• the piezoelectric element is disposed on the diaphragm, the inner edge of the piezoelectric element overlaps the pressure chamber, and the outer edge of the piezoelectric element overlaps the sidewall of the pressure chamber,
• a shape of the inner edge of the piezoelectric element is substantially same as a first rectangle, which includes the inner edge in plan view,
• a shape of an inner periphery of the sidewall of the pressure chamber is substantially same as a second rectangle, which includes the inner periphery of the sidewall in plan view,
• each of a width and a length of the second rectangle is greater than a respective width and length of the first rectangle, and
• one side of the first rectangle and one side of the second rectangle are parallel to each other and also parallel to a crystal orientation <010> in the crystal plane.