Various embodiments may provide an electromechanical responsive film. The electromechanical responsive film may include a composition including sodium (Na), potassium (K), niobium (Nb) and oxygen (O). The composition may have a formula (Na.sub.xK.sub.y)NbO.sub.3-δ, wherein 0≤x<1, wherein 0≤y<1, and wherein 0<x+y<1. The composition may satisfy at least one condition selected from a group consisting of a first condition of (x+y+4)/2≤(3−δ)≤(x+y+5)/2 and a second condition of 0<δ<1.

Organic-inorganic hybrid perovskite has demonstrated tremendous potential for the next generation of electronic and optoelectronic devices due to their remarkable carrier dynamics. However, current studies of electronic and optoelectronic devices have been focused on polycrystalline materials, due to the challenges in synthesizing device compatible high quality single crystalline materials. Here, we firstly report the epitaxial growth of single crystal hybrid perovskites with controlled locations, morphologies, and orientations, using combined strategies of lithography, homoepitaxy, and low temperature solution method. The crystals grow following a layer-by-layer model under controlled growth parameters. The process is robust and can be readily scaled up. The as-grown epitaxial single crystals were integrated in an array of light emitting diodes, each crystal as a pixel with enhanced quantum efficiencies. This capability opens up new opportunities for designing and fabricating a diverse range of high performance electronic and optoelectronic devices using crystalline hybrid perovskites.

Organic-inorganic hybrid perovskite has demonstrated tremendous potential for the next generation of electronic and optoelectronic devices due to their remarkable carrier dynamics. However, current studies of electronic and optoelectronic devices have been focused on polycrystalline materials, due to the challenges in synthesizing device compatible high quality single crystalline materials. Here, we firstly report the epitaxial growth of single crystal hybrid perovskites with controlled locations, morphologies, and orientations, using combined strategies of lithography, homoepitaxy, and low temperature solution method. The crystals grow following a layer-by-layer model under controlled growth parameters. The process is robust and can be readily scaled up. The as-grown epitaxial single crystals were integrated in an array of light emitting diodes, each crystal as a pixel with enhanced quantum efficiencies. This capability opens up new opportunities for designing and fabricating a diverse range of high performance electronic and optoelectronic devices using crystalline hybrid perovskites.

A relaxor-PT based piezoelectric crystal is disclosed, comprising the general formula of (Pb.sub.1-1.5xM.sub.x){[(M.sub.I,M.sub.II).sub.1-z(M.sub.I′,M.sub.II′).sub.z].sub.1-yTi.sub.y}O.sub.3, wherein: M is a rare earth cation; M.sub.I is selected from the group consisting of Mg.sup.2+, Zn.sup.2+, Yb.sup.3+, Sc.sup.3+, and In.sup.3+; M.sub.II is Nb.sup.5+; M.sub.I′ is selected from the group consisting of Mg.sup.2+, Zn.sup.2+, Yb.sup.3+, Sc.sup.3+, In.sup.3+, and Zr.sup.4; M.sub.II′ is Nb.sup.5+ or Zr.sup.4+; 0<x≤0.05; 0.02<y<0.7; and 0≤z≤1, provided that if either M.sub.I′ or M.sub.II′ is Zr.sup.4+, both M.sub.I′ and M.sub.II′ are Zr.sup.4+. A method for forming the relaxor-PT based piezoelectric crystal is disclosed, comprising pre-synthesizing precursor materials by calcining mixed oxides, mixing the precursor materials with single oxides and calcining to form a feeding material, and growing the relaxor-PT based piezoelectric crystal having the general formula of (Pb.sub.1-1.5xM.sub.x){[(M.sub.I,M.sub.II).sub.1-z(M.sub.I′,M.sub.II′).sub.z].sub.1-yTi.sub.y}O.sub.3 from the feeding material by a Bridgman method.

A relaxor-PT based piezoelectric crystal is disclosed, comprising the general formula of (Pb.sub.1-1.5xM.sub.x){[(M.sub.I,M.sub.II).sub.1-z(M.sub.I′,M.sub.II′).sub.z].sub.1-yTi.sub.y}O.sub.3, wherein: M is a rare earth cation; M.sub.I is selected from the group consisting of Mg.sup.2+, Zn.sup.2+, Yb.sup.3+, Sc.sup.3+, and In.sup.3+; M.sub.II is Nb.sup.5+; M.sub.I′ is selected from the group consisting of Mg.sup.2+, Zn.sup.2+, Yb.sup.3+, Sc.sup.3+, In.sup.3+, and Zr.sup.4; M.sub.II′ is Nb.sup.5+ or Zr.sup.4+; 0<x≤0.05; 0.02<y<0.7; and 0≤z≤1, provided that if either M.sub.I′ or M.sub.II′ is Zr.sup.4+, both M.sub.I′ and M.sub.II′ are Zr.sup.4+. A method for forming the relaxor-PT based piezoelectric crystal is disclosed, comprising pre-synthesizing precursor materials by calcining mixed oxides, mixing the precursor materials with single oxides and calcining to form a feeding material, and growing the relaxor-PT based piezoelectric crystal having the general formula of (Pb.sub.1-1.5xM.sub.x){[(M.sub.I,M.sub.II).sub.1-z(M.sub.I′,M.sub.II′).sub.z].sub.1-yTi.sub.y}O.sub.3 from the feeding material by a Bridgman method.

Metal oxides and method for forming the method oxides are provided. The disclosed functional metal oxides are single crystalline or polycrystalline metal oxides, such as, for example, SrVO.sub.3, and have dimensions, phase purity, and crystalline quality previously unachievable. The disclosed methods include a combination of a gas atmosphere, vacuum sintering, and laser-based directional solidification of a seed rod in contact with a feed rod that is scalable for production quantities.

A method for manufacturing epitaxial films with multiple stress states, comprising steps of: providing a first single crystal substrate, and forming a sacrificial layer and a first epitaxial film on the first single crystal substrate, wherein the first epitaxial film is made of a first material;

removing the sacrificial layer to separate the first epitaxial film from the first single crystal substrate; transferring the first epitaxial film to a second single crystal substrate, wherein the second single crystal substrate is made of a second material, a partial surface of the second single crystal substrate being overlapped by the first epitaxial film; applying epitaxies onto the first epitaxial film and the second single crystal substrate to form a second epitaxial film on the first epitaxial film and the second single crystal substrate.

A method for manufacturing epitaxial films with multiple stress states, comprising steps of: providing a first single crystal substrate, and forming a sacrificial layer and a first epitaxial film on the first single crystal substrate, wherein the first epitaxial film is made of a first material;

removing the sacrificial layer to separate the first epitaxial film from the first single crystal substrate; transferring the first epitaxial film to a second single crystal substrate, wherein the second single crystal substrate is made of a second material, a partial surface of the second single crystal substrate being overlapped by the first epitaxial film; applying epitaxies onto the first epitaxial film and the second single crystal substrate to form a second epitaxial film on the first epitaxial film and the second single crystal substrate.

There are provided a piezoelectric film-attached substrate and piezoelectric element, which include, on a substrate in the following order, a lower electrode layer, a piezoelectric film containing a perovskite-type oxide containing lead as a main component of an A site, and a buffer layer, where the buffer layer contains a metal oxide represented by M.sub.dN.sub.1-dO.sub.e. Here, M consists of one or more metal elements substitutable for the A site of the perovskite-type oxide and has an electronegativity of less than 0.95. In a case of 0<d<1 and in a case where the electronegativity is denoted by X, 1.41X−1.05≤d≤A1.Math.exp(−X/t1)+y0, where A1=1.68×10.sup.12, t1=0.0306, and y0=0.59958.

A method for method for manufacturing a rutile titanium dioxide layer according to the inventive concept includes forming a sacrificial layer on a substrate, and depositing a titanium dioxide (TiO.sub.2) material on the sacrificial layer. The sacrificial layer includes a metal oxide of a rutile phase. An amount of oxygen vacancy of the sacrificial layer after depositing the titanium dioxide material is greater than an amount of oxygen vacancy of the sacrificial layer before depositing the titanium dioxide material. The metal oxide includes a metal different from titanium (Ti).