Liquid-jet head, method for manufacturing the liquid-jet head, and liquid-jet apparatus

A method for manufacturing a liquid-jet head, comprising the steps of:

• after forming a lower electrode film, forming a piezoelectric layer comprising a plurality of layers of ferroelectric films, on the lower electrode film, which is formed via a vibration plate on a passage-forming substrate in which a pressure generating chamber communicating with a nozzle orifice for ejecting liquid is to be formed;
• and
• after forming an upper electrode film on the piezoelectric layer, forming a piezoelectric element by means of patterning the upper electrode film and the piezoelectric layer,
• wherein the step of forming the piezoelectric layer comprises the steps of:
• forming a first ferroelectric film, which is a lowermost layer of the plurality of layers of ferroelectric films, by means of forming on the lower electrode film a ferroelectric precursor film having a predetermined thickness, and firing the ferroelectric precursor film;
• patterning the lower electrode film and the first ferroelectric film such that one end portion of the lower electrode film and one end portion of the first ferroelectric film are located in a region facing a region of the pressure generating chamber and such that an end face of the end portion of the lower electrode film and an end face of the end portion of the first ferroelectric film are sloped at a predetermined angle with respect to the vibration plate;
• and
• forming the plurality of layers of ferroelectric films by means of repeating, a plurality of times, a step of forming at least a single layer of ferroelectric precursor film on the first ferroelectric film and firing the ferroelectric precursor film(s).

An actuator device comprising:

• a substrate;
• a vibration plate provided on one face of the substrate;
• and
• a piezoelectric element provided on the vibration plate and including a lower electrode, a piezoelectric layer, and an upper electrode,
• wherein the lower electrode of the piezoelectric element is formed through patterning;
• the piezoelectric layer comprises a plurality of layers of ferroelectric films;
• a first ferroelectric film, which is a lowermost layer of the plurality of layers of ferroelectric films, is provided only on the lower electrode such that an end face thereof is aligned with the end face of the lower electrode;
• the end face of the first ferroelectric film and the end face of the lower electrode are sloped at an angle of 10° to 50° with respect to the vibration plate;
• and
• other ferroelectric films formed on the first ferroelectric film are provided in such a manner as to overlie the sloped end face of the lower electrode and the sloped end face of the first ferroelectric film.