Piezoelectric device, liquid ejecting head, and liquid ejecting apparatus

A piezoelectric device comprising:

• a pressure chamber;
• a piezoelectric element;
• and
• a vibration plate arranged between the pressure chamber and the piezoelectric element and forming a wall surface which intersects a side wall of the pressure chamber,
• wherein the piezoelectric element is provided with a first electrode on the vibration plate side, a second electrode on an opposite side of the vibration plate with respect to the first electrode, and a piezoelectric layer interposed between the first electrode and the second electrode,
• the vibration plate has a first portion overlapping the piezoelectric element in a plan view and a second portion having a thickness smaller than that of the first portion and overlapping an inner peripheral surface of the side wall of the pressure chamber in a plan view, and
• a side surface of the piezoelectric layer which intersects the first electrode has a first surface inclined at a first angle with respect to a surface of the vibration plate on the pressure chamber side and a second surface inclined at a second angle smaller than the first angle, wherein the second angle is greater than zero degrees.

A piezoelectric device comprising:

• a pressure chamber;
• a piezoelectric element;
• and
• a vibration plate arranged between the pressure chamber and the piezoelectric element and forming a wall surface which intersects a side wall of the pressure chamber,
• wherein the piezoelectric element is provided with a first electrode on the vibration plate side, a second electrode on an opposite side of the vibration plate with respect to the first electrode, and a piezoelectric layer interposed between the first electrode and the second electrode,
• the first electrode has a first portion overlapping the piezoelectric layer in a plan view and a second portion having a thickness smaller than that of the first portion and overlapping an inner peripheral surface of the side wall of the pressure chamber in a plan view,
• a side surface of the piezoelectric layer which intersects the first electrode has a first surface inclined at a first angle with respect to a surface of the vibration plate on the pressure chamber side,
• the first electrode has a second surface, between the first portion and the second portion, inclined at a second angle smaller than the first angle with respect to a surface of the vibration plate on the pressure chamber side, and
• an end portion of the second surface of the vibration plate overlaps the side wall of the pressure chamber in a plan view.

A piezoelectric device comprising:

• a pressure chamber;
• a piezoelectric element;
• and
• a vibration plate arranged between the pressure chamber and the piezoelectric element and forming a wall surface which intersects a side wall of the pressure chamber,
• wherein the piezoelectric element is provided with a first electrode on the vibration plate side, a second electrode on an opposite side of the vibration plate with respect to the first electrode, and a piezoelectric layer interposed between the first electrode and the second electrode,
• the first electrode has a first portion overlapping the piezoelectric layer in a plan view and a second portion having a thickness smaller than that of the first portion and overlapping an inner peripheral surface of the side wall of the pressure chamber in a plan view, and
• a side surface of the piezoelectric layer which intersects the first electrode has a first surface inclined at a first angle with respect to a surface of the vibration plate on the pressure chamber side and a second surface inclined at a second angle smaller than the first angle.