Patent ID: 6217979
Filing Date: 2001-04-17
Classification: C04B,H01L,H04R,Y10T

Abstract:
A piezoelectric/electrostrictive film element comprising:a ziroconia substrate having at least one window, and a diaphragm portion formed as an integral part of said ziroconia substrate and closing each of said at least one window and where said diaphragm portion contains an alumina component in an amount of 1.1-5.0 parts by weight before firing; anda piezoelectric/electrostrictive unit film including a lower electrode, a piezoelectric/electrostrictive layer and an upper electrode, which are formed in the order of description on an outer surface of said diaphragm portion by a film-forming process, said piezoelectric/electrostrictive layer being formed using a piezoelectric/electrostrictive material which contains magnesia or a component which gives magnesia in an independent form or in a compound form;wherein said diaphragm portion and said lower electrode define an interface directly under said piezoelectric/electrostrictive layer, and particles consisting essentially of a compound of alumina and magnesia exist at least on said interface at an occupied area ratio of 10% or greater, wherein occupied area ratio is defined by (%)=(A/A.sub.0).times.100, A.sub.0 being the surface area of the diaphragm portion which corresponds to that of the piezoelectric/electrostrictive layer under which the lower electrode was formed, and A being the total area of particles consisting essentially of the alumina-magnesia compound which exist on the surface area of the diaphragm portion with the piezoelectric/electrostrictive unit being removed, which surface area corresponds to that of the lower electrode right under the layer, to thereby relax said diaphragm portion during sintering of said piezoelectric/electrostrictive layer to facilitate sintering of said piezoelectric/electrostrictive layer.