Method of manufacturing piezoelectric thin film device and piezoelectric thin film device

摘要

Method of producing a piezoelectric thin film device comprises a step of forming an insulating layer ( 12 ) capable of being etched by a specific chemical substance on the upper surface of a substrate ( 11 ); a step of forming a sacrificial layer ( 13 ) made of a substance having a higher etching rate by the specific chemical substance than the insulating layer on a partial region of the insulating layer; a step of forming a lower electrode ( 15 ) on a region including the sacrificial layer; a step of forming the piezoelectric thin film ( 16 ) on a region including a part of the lower electrode; a step of forming an upper electrode ( 17 ) on a region including a part of the piezoelectric thin film; a step of forming via hole ( 18 ), which penetrates the piezoelectric thin film and lower electrode, so as to expose a part of the sacrificial layer; and a step of forming a space ( 20 ) for oscillation by etching both the sacrificial layer and the insulating layer with the same specific chemical substance by introducing the specific chemical substance through the via hole.