Provided is a composite substrate for a surface acoustic wave device in which a chip is hardly generated at an outer peripheral edge of an electric material layer and peeling is hardly generated from the outer peripheral edge. The composite substrate for a surface acoustic wave device is a composite substrate in which a piezoelectric material single crystal thin film and a supporting substrate are bonded at a bonding surface. The supporting substrate has a closed first contour line, the bonding surface has a closed second contour line, and the piezoelectric material single crystal thin film has a closed third contour line. When the first contour line and the third contour line are projected perpendicularly to a plane including the bonding surface, the projection image of the first contour line is located outside the second contour line, and the projection image of the third contour line is located inside the second contour line.

A method of manufacturing an integrated circuit. This method includes forming an epitaxial material comprising single crystal piezo material overlying a surface region of a substrate to a desired thickness and forming a trench region to form an exposed portion of the surface region through a pattern provided in the epitaxial material. Also, the method includes forming a topside landing pad metal and a first electrode member overlying a portion of the epitaxial material and a second electrode member overlying the topside landing pad metal. Furthermore, the method can include processing the backside of the substrate to form a backside trench region exposing a backside of the epitaxial material and the landing pad metal and forming a backside resonator metal material overlying the backside of the epitaxial material to couple to the second electrode member overlying the topside landing pad metal.

A subtractive forming method for piezoresistive material stacks includes applying an etch chemistry to an exposed first portion of a piezoresistive material stack. The etch chemistry includes a citric acid component for removing a first element of a piezoelectric layer of the piezoresistive material stack selectively to a surface oxide. At least one second element of the piezoelectric layer remains. The method further includes heating the piezoresistive material stack after said applying the etch chemistry to vaporize the at least one second element. A second portion of the piezoresistive material stack is protected from the removal and the heating by a mask.

Thermally stable piezoelectric polymer foams (ferroelectrets) with high piezoelectric activity for sensing and actuation. The invention further includes a method of fabricating such foams in an environmentally friendly manner.

A method of manufacturing an integrated circuit. This method includes forming an epitaxial material comprising single crystal piezo material overlying a surface region of a substrate to a desired thickness and forming a trench region to form an exposed portion of the surface region through a pattern provided in the epitaxial material. Also, the method includes forming a topside landing pad metal and a first electrode member overlying a portion of the epitaxial material and a second electrode member overlying the topside landing pad metal. Furthermore, the method can include processing the backside of the substrate to form a backside trench region exposing a backside of the epitaxial material and the landing pad metal and forming a backside resonator metal material overlying the backside of the epitaxial material to couple to the second electrode member overlying the topside landing pad metal.

A material deposition method comprising: providing a substrate; forming a film of HfO2 by chemical solution deposition, CSD, on the substrate; depositing a solution of PbTiO3 on the film of HfO2; depositing a layer of Pb(Zrx,Ti1-x)O3 on the seed layer, where Ox1; and forming interdigitated electrodes on the Pb(Zrx,Ti1-x)O 3 layer. Also a ferroelectric microsystem obtained by this deposition method. Experiments show an improved fatigue resistance for such a microsystem.

A material deposition method comprising: providing a substrate; forming a film of HfO2 by chemical solution deposition, CSD, on the substrate; depositing a solution of PbTiO3 on the film of HfO2; depositing a layer of Pb(Zrx,Ti1-x)O3 on the seed layer, where Ox1; and forming interdigitated electrodes on the Pb(Zrx,Ti1-x)O 3 layer. Also a ferroelectric microsystem obtained by this deposition method. Experiments show an improved fatigue resistance for such a microsystem.

An electromechanical conversion element includes: a first electrode, an electromechanical conversion layer, and a second electrode provided on a substrate; a first high-temperature durable layer that contains a metal oxide between the first electrode and the electromechanical conversion layer; and a second high temperature durable layer that containing a metal oxide between the electromechanical conversion layer and the second electrode. The electromechanical conversion layer contains a perovskite-type crystal. Upon diffraction peak intensities of a (001) plane, a (101) plane, and a (111) plane in X-ray diffraction measurement of the electromechanical conversion layer being I(001), I(101), and I(111), respectively, a degree of orientation of the (001) plane represented by {I(001))/(I(001)+I(101)+I(111)}?100% is 99.0% or more.

An electromechanical conversion element includes: a first electrode, an electromechanical conversion layer, and a second electrode provided on a substrate; a first high-temperature durable layer that contains a metal oxide between the first electrode and the electromechanical conversion layer; and a second high temperature durable layer that containing a metal oxide between the electromechanical conversion layer and the second electrode. The electromechanical conversion layer contains a perovskite-type crystal. Upon diffraction peak intensities of a (001) plane, a (101) plane, and a (111) plane in X-ray diffraction measurement of the electromechanical conversion layer being I(001), I(101), and I(111), respectively, a degree of orientation of the (001) plane represented by {I(001))/(I(001)+I(101)+I(111)}?100% is 99.0% or more.

A joining method is for producing a sound transducer system. The method includes: providing a piezoelectric material and a plurality of components, each of the components being characterized by a solidus temperature; arranging the piezoelectric material and the plurality of components in the form of a stack, so that adjacent to a front face of the piezoelectric material there is a front stack part and adjacent to a rear face of the piezoelectric material there is a rear stack part; and consolidating the stack by the introduction of heat and pressure for a predetermined period of time, none of the solidus temperatures of the plurality of components being exceeded during the consolidation; and, during the consolidation, the piezoelectric material being directly acoustically coupled to an immediately adjacent component of the front and/or rear stack part.