Liquid ejecting head, liquid ejecting apparatus, piezoelectric element, and method for manufacturing piezoelectric element
A flow channel substrate has pressure chambers, and the pressure chambers communicate with nozzle openings configured to eject liquid. Each of piezoelectric elements on the flow channel substrate has a piezoelectric layer, a pair of electrodes, and a wiring layer coupled to the electrodes. The wiring layer has a first layer on the flow channel substrate side and a second layer on the first layer. The first layer contains palladium and is formed by pretreatment, whereas the second layer contains nickel and is formed by electroless plating.
1. A liquid ejecting head comprising:
a flow channel substrate, the flow channel substrate including a pressure chamber communicating with a nozzle opening configured to eject liquid; and
a piezoelectric element, the piezoelectric element provided to the flow channel substrate and having a piezoelectric layer, a pair of electrodes, and a wiring layer coupled to at least one of the electrodes,
the wiring layer including:
a first layer containing palladium,
a second layer on the first layer, the second layer containing nickel,
a third layer on the second layer, the third layer containing palladium, and
a fourth layer on the third layer, the fourth layer containing gold.
2. The liquid ejecting head according to claim 1 , wherein the pair of electrodes are a first electrode on a flow channel substrate side and a second electrode on a side of the piezoelectric layer opposite the flow channel substrate.
3. The liquid ejecting head according to claim 2 , wherein:
the first electrode includes a plurality of separate electrodes for a plurality of active sections, i.e., practical actuating elements, the separate electrodes electrically isolated from each other; and
the second electrode serves as a common electrode for the active sections, the common electrode electrically continuous.
4. The liquid ejecting head according to claim 1 , wherein the pretreatment for forming the first layer is dip coating.
5. A liquid ejecting apparatus comprising the liquid ejecting head according to claim 1 .
6. A liquid ejecting apparatus comprising the liquid ejecting head according to claim 2 .
7. A liquid ejecting apparatus comprising the liquid ejecting head according to claim 3 .
8. A liquid ejecting apparatus comprising the liquid ejecting head according to claim 4 .
9. A piezoelectric element comprising:
a piezoelectric layer;
a pair of electrodes; and
a wiring layer coupled to at least one of the electrodes,
the wiring layer including:
a first layer containing palladium,
a second layer on the first layer, the second layer containing nickel,
a third layer on the second layer, the third layer containing palladium, and
a fourth layer on the third layer, the fourth layer containing gold.
10. A method for manufacturing a piezoelectric element having a piezoelectric layer, a pair of electrodes, and a wiring layer coupled to the electrodes, the method comprising:
forming a mask on the electrodes with the electrodes exposed, the mask perforated at least in a region where the wiring layer is to be formed;
forming a palladium-containing first layer by pretreatment;
removing the mask; and
forming a nickel-containing second layer on the first layer by electroless plating.
11. The method for manufacturing a piezoelectric element according to claim 10 , the method further comprising:
forming a palladium-containing third layer on the second layer by electroless plating; and
forming a gold-containing fourth layer on the third layer by electroless plating.