Disclosed is a method for producing a polymeric ferroelectric material. The method can include (a) obtaining a polymeric ferroelectric precursor material, and (b) subjecting the polymeric ferroelectric precursor material to pulsed electromagnetic radiation sufficient to form a polymeric ferroelectric material having ferroelectric hysteresis properties, wherein the polymeric ferroelectric precursor material, prior to step (b), has not previously been subjected to a thermal treatment for more than 55 minutes.

A method for forming a LaNiO.sub.3 thin film is provided, the method including: a step of forming a coating film by coating a substrate surface which is coated with a Pt electrode with a LaNiO.sub.3 thin film-forming liquid composition and drying the LaNiO.sub.3 thin film-forming liquid composition in a state where amounts of H.sub.2, H.sub.2O, and CO adsorbed on the substrate surface per 1 cm.sup.2 are 1.010.sup.10 g or less, 2.710.sup.10 g or less, and 4.210.sup.10 g or less, respectively; a step of pre-baking the coating film; and a step of forming a LaNiO.sub.3 thin film by baking the pre-baked coating film.

A substrate for piezoelectric body formation has a base substrate layer containing at least SiO.sub.2 or SiN in the surface, an intermediate layer containing at least one of Ti and TiO.sub.2 on the base substrate layer, and an electrode layer containing Pt on the intermediate layer, in which the film thickness of the electrode layer is 40 nm or more and 1000 nm or less and Ti is not detected in the surface of the electrode layer by an elemental quantitative analysis method.

A method of forming an acoustic resonator includes forming a seed layer on a first electrode layer, forming a piezoelectric layer directly on a surface of the seed layer, and forming a second electrode layer on the piezoelectric layer. The piezoelectric layer includes multiple crystals of piezoelectric material, and the seed layer causes crystal axis orientations of the crystals to be substantially perpendicular to the surface of the seed layer.

A piezoelectric thin film element includes a substrate, a vibration plate provided on the substrate, a lower electrode provided on the vibration plate, the lower electrode including at least a platinum metal film or an iridium metal film, a piezoelectric film provided on the lower electrode, the piezoelectric film including a polycrystalline body, and an upper electrode provided on the piezoelectric film, the lower electrode being provided on an upper portion of a titanium oxide film formed on the vibration plate, the lower electrode including a platinum metal film or an iridium metal film formed on the titanium oxide film and conductive oxide formed on the platinum metal film or the iridium metal film, and the platinum metal film or the iridium metal film being a precise film.

Composite material comprising a fluoropolymer matrix and a filler formed of nanoparticles of a ceramic of the BZT-BXT type wherein X is selected from Ca, Sn, and Mn and a is a molar fraction selected in the range between 0.10-0.90 doped with at least one doping element selected from the group consisting of Nb, La, Mn, Nd and W, wherein when X is Mn, the doping element is not Mn, wherein said nanoparticles have an average diameter comprised between 10 and 25% by weight on the total weight of the composite. The composite material is used to form a thin film usable as a piezoelectric material with inductive properties in electronic components, for example acoustic sensors such as microphones, and energy harvesting transducers.

A complex oxide includes a chemical compound represented by ABO.sub.3 (Chemical Formula 1). In the Chemical Formula 1, A is one or more elements selected from Ba, Ca, and Sr; and B is one or more elements selected from Ti, Zr, Hf, and Sn. When a field having a size of 1 m1 m on a surface of the complex oxide is observed with an atomic force microscope (AFM), a typical particle size is greater than or equal to 300 nm and less than 660 nm. Here, the typical particle size is a maximum length of a maximum particle observed in the field.

An RF integrated circuit device can includes a substrate and a High Electron Mobility Transistor (HEMT) device on the substrate including a ScAlN layer configured to provide a buffer layer of the HEMT device to confine formation of a 2DEG channel region of the HEMT device. An RF piezoelectric resonator device can be on the substrate including the ScAlN layer sandwiched between a top electrode and a bottom electrode of the RF piezoelectric resonator device to provide a piezoelectric resonator for the RF piezoelectric resonator device.

An RF integrated circuit device can includes a substrate and a High Electron Mobility Transistor (HEMT) device on the substrate including a ScAlN layer configured to provide a buffer layer of the HEMT device to confine formation of a 2DEG channel region of the HEMT device. An RF piezoelectric resonator device can be on the substrate including the ScAlN layer sandwiched between a top electrode and a bottom electrode of the RF piezoelectric resonator device to provide a piezoelectric resonator for the RF piezoelectric resonator device.

At least two types of dielectric materials such as oxide nanosheets having a layered perovskite structure that differ from each other are laminated, and the nanosheets are bonded to each other via an ionic material, thereby producing a superlattice structure-having ferroelectric thin film. Having the layered structure, the film can exhibit ferroelectricity as a whole, though not using a ferroelectric material therein. Accordingly, there is provided a ferroelectric film based on a novel principle, which is favorable for ferroelectric memories and others and which is free from a size effect even though extremely thinned.