Methods for producing ferroelectric device are described. A method includes positioning an organic polymeric ferroelectric layer between two conductive materials to form a stack. The stack can be subjected to a 2-step heat treating process. The first heat treating step transforms the organic polymeric ferroelectric precursor to a ferroelectric material having ferroelectric hysteresis properties, and the second heat treating step densities the ferroelectric material to obtain the ferroelectric device. The thin film ferroelectric device can include a thin film ferroelectric capacitor, a thin film ferroelectric transistor, or a thin film ferroelectric diode.

Provided is a method for forming a ferroelectric film of a metal oxide having a fluorite-type structure at a low temperature of lower than 300 C., and a ferroelectric film obtained at a low temperature. The present invention provides a production method of a ferroelectric film comprising a crystalline metal oxide having a fluorite-type structure of an orthorhombic crystal phase, which comprises using a film sputtering method comprising sputtering a target at a substrate temperature of lower than 300 C., to deposit on the substrate a film of a metal oxide which is capable of having a fluorite-type structure of an orthorhombic crystal phase, and having a subsequent thermal history of said film of lower than 300 C.; or applying an electric field to said film after said deposition or after said thermal history of lower than 300 C. Also provided are the ferroelectric film, which is formed on an organic substrate, glass, or metal substrate, which can be used only at low temperatures, and a ferroelectric element and a ferroelectric functional element or device using the ferroelectric film.

Provided is a method for forming a ferroelectric film of a metal oxide having a fluorite-type structure at a low temperature of lower than 300 C., and a ferroelectric film obtained at a low temperature. The present invention provides a production method of a ferroelectric film comprising a crystalline metal oxide having a fluorite-type structure of an orthorhombic crystal phase, which comprises using a film sputtering method comprising sputtering a target at a substrate temperature of lower than 300 C., to deposit on the substrate a film of a metal oxide which is capable of having a fluorite-type structure of an orthorhombic crystal phase, and having a subsequent thermal history of said film of lower than 300 C.; or applying an electric field to said film after said deposition or after said thermal history of lower than 300 C. Also provided are the ferroelectric film, which is formed on an organic substrate, glass, or metal substrate, which can be used only at low temperatures, and a ferroelectric element and a ferroelectric functional element or device using the ferroelectric film.

A dielectric having a high dielectric property with low hysteresis loss, and having high flexibility, the dielectric comprises a polyurethane elastomer and an ionic liquid in the polyurethane elastomer, the polyurethane elastomer comprises a matrix and a domain dispersed in the matrix, and the domain comprises a specific polyether structure.

A piezoelectric device comprising a transparent substrate; a transparent barrier layer on the substrate; a transparent piezoelectric layer on the transparent barrier layer; a transparent layer of interdigitated electrodes on the transparent piezoelectric layer; wherein the piezoelectric device further comprises a transparent dielectric layer at least on the portion of piezoelectric layer that is between successive fingers of the transparent layer of interdigitated electrodes, the transparent dielectric layer having a refractive index lower than a refractive index of the transparent layer of interdigitated electrodes and a dielectric strength superior to 3 MV/m.

A piezoelectric device comprising a transparent substrate; a transparent barrier layer on the substrate; a transparent piezoelectric layer on the transparent barrier layer; a transparent layer of interdigitated electrodes on the transparent piezoelectric layer; wherein the piezoelectric device further comprises a transparent dielectric layer at least on the portion of piezoelectric layer that is between successive fingers of the transparent layer of interdigitated electrodes, the transparent dielectric layer having a refractive index lower than a refractive index of the transparent layer of interdigitated electrodes and a dielectric strength superior to 3 MV/m.

A method for manufacturing a piezoelectric element for generating electricity upon flexing of the element including the steps spin-coating a first substrate layer onto a support substrate; depositing a first electrode film onto the first substrate layer; spin coating polyvinylidene fluoride (PVDF) containing solution on the first electrode film to result in a PVDF film; annealing the PVDF film; depositing a second electrode film onto the PVDF film; spin-coating a second substrate layer on top of the second electrode film; forming a hole through the first and second substrate layers; filling the hole with silver paste to contact to the first and second electrode layers; peeling a resulting substrate/electrode/PVDF/electrode/substrate device from the support substrate; and placing a drop of silver paste in the hole formed in the first substrate layer.

A method for manufacturing a piezoelectric element for generating electricity upon flexing of the element including the steps spin-coating a first substrate layer onto a support substrate; depositing a first electrode film onto the first substrate layer; spin coating polyvinylidene fluoride (PVDF) containing solution on the first electrode film to result in a PVDF film; annealing the PVDF film; depositing a second electrode film onto the PVDF film; spin-coating a second substrate layer on top of the second electrode film; forming a hole through the first and second substrate layers; filling the hole with silver paste to contact to the first and second electrode layers; peeling a resulting substrate/electrode/PVDF/electrode/substrate device from the support substrate; and placing a drop of silver paste in the hole formed in the first substrate layer.

A piezoelectric bio-organic films resembling ceramic-based piezoelectric films, and also a fabrication method thereof. In particular, the bio-organic piezoelectric films are formed by compact nanocrystals resembling the inorganic ceramic structure, where nanocrystallization on biomaterials and in-situ electric field are applied to facilitate domain orientation alignment across the entire films. The present fabrication method provides flexibility to tune various parameters of the resulting bio-organic films according to the needs, and therefore is substantially applicable to a wide range of biomaterials to form piezoelectric bio-organic films comparable to those formed by conventional piezoceramics in terms of piezoelectricity, thermostability and durability.

A piezoelectric bio-organic films resembling ceramic-based piezoelectric films, and also a fabrication method thereof. In particular, the bio-organic piezoelectric films are formed by compact nanocrystals resembling the inorganic ceramic structure, where nanocrystallization on biomaterials and in-situ electric field are applied to facilitate domain orientation alignment across the entire films. The present fabrication method provides flexibility to tune various parameters of the resulting bio-organic films according to the needs, and therefore is substantially applicable to a wide range of biomaterials to form piezoelectric bio-organic films comparable to those formed by conventional piezoceramics in terms of piezoelectricity, thermostability and durability.