Piezoelectric actuator, method for producing piezoelectric actuator, liquid transporting apparatus, and method for producing liquid transporting apparatus

A method for manufacturing a piezoelectric actuator for a liquid transporting apparatus, the piezoelectric actuator being provided on a surface of a channel unit having a plurality of pressure chambers arranged along a plane, and selectively changing volumes of the plurality of pressure chambers, the method comprising:

• a piezoelectric layer forming step of forming a piezoelectric layer on a surface of a vibration plate, which covers the pressure chambers and which has a first electrode, the piezoelectric layer being formed on the surface of vibration plate on a side of the first electrode, the first electrode being provided at an area of the vibration plate which faces the pressure chambers and which is on a surface of the vibration plate opposite to the pressure chambers;
• a thickness measuring step of measuring thicknesses of the piezoelectric layer at areas of the piezoelectric layer, each of the areas overlapping with one of the pressure chambers and the first electrode in a plane view;
• and
• a step of forming second electrodes on a surface of the piezoelectric layer on a side opposite to the first electrode while adjusting lengths in a predetermined direction of the second electrodes according to the measured thicknesses of the piezoelectric layer.

A liquid transporting apparatus including a channel unit having a plurality of pressure chambers arranged along a plane, and a piezoelectric actuator which is provided on a surface of the channel unit and which selectively changes volumes of the plurality of pressure chambers, the piezoelectric actuator comprising:

• a vibration plate covering the plurality of pressure chambers;
• a piezoelectric layer arranged on a side of the vibration plate opposite to the plurality of pressure chambers;
• a first electrode provided at an area of the piezoelectric layer on a side of the plurality of pressure chambers, the area facing the plurality of pressure chambers;
• and
• second electrodes provided at areas of the piezoelectric layer on a side opposite to the plurality of pressure chambers, each of the areas facing one of the pressure chambers and the first electrode;
• wherein lengths in a predetermined direction of the second electrodes at portions facing the first electrode differ according to lengths of the piezoelectric layer at portions each of which is interposed between the first electrode and one of the second electrodes.

A method for manufacturing a liquid transporting apparatus including a channel unit having a plurality of pressure chambers arranged along a plane, and a piezoelectric actuator which is provided on a surface of the channel unit and which selectively changes volumes of the plurality of pressure chambers, the method comprising:

• a piezoelectric layer forming step of forming a piezoelectric layer on a surface of a vibration plate which covers the pressure chambers and which has a first electrode provided on a surface of the vibration plate, the piezoelectric layer being formed on the surface of the vibration plate provided with the first electrode, the first electrode being provided at an area of the vibration plate which faces the pressure chambers, the area being on a side of the vibration plate opposite to the pressure chambers;
• a thickness measuring step of measuring thicknesses of the piezoelectric layer at areas each of which overlaps with one of the pressure chambers and the first electrode in a plane view;
• and
• a step of forming second electrodes on a surface of the piezoelectric layer on a side opposite to the first electrode by adjusting lengths in a predetermined direction of the second electrodes according to the measured thicknesses of the piezoelectric layer.