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AssigneeNational Institute of Advanced Industrial Science and Technology
InventorsMorito Akiyama, Naohiro Ueno, Hiroshi Tateyama, Noriyuki Kuwano
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A lower electrode is formed on a silica glass substrate or a stainless substrate. Through a sputtering process, a thin film of aluminum nitride and/or zinc oxide is formed on the lower substrate so that the degree of dipole-orientation becomes 55% or more, and thereby a piezoelectric thin film is formed. And an upper electrode is formed on the piezoelectric thin film. A piezoelectric device has a piezoelectric layer made of aluminum nitride and/or zinc oxide. Aluminum nitride and zinc oxide with a crystal structure have inborn piezoelectric characteristics because their crystal structures are not symmetrical, they do not have Curie temperature unlike ferroelectrics, and in aluminum nitride and zinc oxide, magnetic transition does not occur even at high temperature, so that they never lose piezoelectric characteristics until crystal melts or sublimates.
A piezoelectric device in which a first electrode layer, a piezoelectric layer and a second electrode layer are laminated on a substrate in this order,
A method for fabricating a piezoelectric device, comprising the steps of:
Dependencies are inferred from the claim text.