Patent ID: 7318277

Claim:
A method of manufacturing a liquid jet head characterized by comprising the steps of: forming a piezoelectric element including a lower electrode, a piezoelectric layer, and an upper electrode on one plane of a passage-forming substrate with a vibration plate interposed therebetween, the passage-forming substrate which is made of a silicon substrate and in which a pressure generating chamber communicating with a nozzle orifice for ejecting liquid and a communicating portion communicating with the pressure generating chamber are formed, and removing a region of the vibration plate where the communicating portion is formed, thus forming a penetrated hole; forming a predetermined metal layer on the one plane of the passage-forming substrate on which the piezoelectric element is formed, thus sealing the penetrated hole with the metal layer, and patterning the metal layer in an area corresponding to the piezoelectric element, thus forming a lead electrode extending from the piezoelectric element; adhering a reservoir-forming plate, in which a reservoir portion communicating with the communicating portion to constitute a part of a reservoir is formed, to the one plane of the passage-forming substrate; wet-etching the passage-forming substrate from the other plane thereof until the vibration plate and the metal layer are exposed, thus forming the pressure generating chamber and the communicating portion; and removing a region of the metal layer corresponding to the penetrated hole by etching to allow the reservoir portion and the communicating portion to communicate with each other.