A layered solid element includes a ferroelectric layer of a crystalline material Li.sub.1−x(Nb.sub.1−yTa.sub.y).sub.1+xO.sub.3+2x−z which has X- or 33° Y-orientation with respect to a substrate of the layered solid element. The ferroelectric layer is grown epitaxially from a buffer layer having of one of the chemical formulae L.sub.kNi.sub.rO.sub.1.5.Math.(k+r)+w or L.sub.n+1Ni.sub.nO.sub.3n+1+δ, where L is a lanthanide element. Such layered solid element may form a thin-film bulk acoustic resonator and be useful for integrated electronic circuits such as RF-filters, or guided optical devices such as integrated optical modulators.

A composite substrate is resistant to the development of cracks, thereby not having deteriorating properties even when exposed to high-temperatures or low temperatures, and a method is provided for producing the composite substrate. The composite substrate 10 of the present invention has a supporting substrate 2, a stress relaxing interlayer 3, and an oxide single-crystal thin film 1 stacked in the listed order. The stress relaxing interlayer 3 has a thermal expansion coefficient between that of the supporting substrate 2 and that of the oxide single-crystal thin film 1.

A composite substrate is resistant to the development of cracks, thereby not having deteriorating properties even when exposed to high-temperatures or low temperatures, and a method is provided for producing the composite substrate. The composite substrate 10 of the present invention has a supporting substrate 2, a stress relaxing interlayer 3, and an oxide single-crystal thin film 1 stacked in the listed order. The stress relaxing interlayer 3 has a thermal expansion coefficient between that of the supporting substrate 2 and that of the oxide single-crystal thin film 1.

A method for forming a lithium niobate- or lithium tantalum-based (LN/LT) layer includes providing a silicon-based substrate, forming nucleation layer on the substrate, and forming the LN/LT layer by epitaxy on the nucleation layer. The nucleation layer is chosen based upon a III-N material. The nucleation layer may be used in a surface acoustic wave device.

A method for forming a lithium niobate- or lithium tantalum-based (LN/LT) layer includes providing a silicon-based substrate, forming nucleation layer on the substrate, and forming the LN/LT layer by epitaxy on the nucleation layer. The nucleation layer is chosen based upon a III-N material. The nucleation layer may be used in a surface acoustic wave device.

A method may include stretching a deformable bounding element into a stretched state. The method may further include coating the deformable bounding element with at least one layer of an anti-reflective material while the deformable bounding element is in the stretched state and assembling an optical lens assembly including the deformable bounding element, such that the optical lens assembly adjusts at least one optical property by controlling a shape of the deformable bounding element. The deformable bounding element may have less tension when in a neutral state than the deformable bounding element has when in the stretched state. The method may additionally include coating the deformable bounding element with at least one layer of an anti-reflective material while the deformable bounding element is not in a stretched state. Various other apparatuses, systems, and methods are also disclosed.

Among other things, piezoelectric materials and methods of their manufacture are described; particularly methods of forming regions of varying crystal structure within a relaxor piezoelectric substrate. Such methods may including heating the piezoelectric substrate above the transition temperature and below the Curie temperature such that a first phase transition occurs to a first crystal structure; rapidly cooling the piezoelectric substrate below the transition temperature at a cooling rate that is sufficiently high for the first crystal structure to persist; and applying an electric field through one or more selected regions of the piezoelectric substrate, such that within the one or more selected regions, a second phase transition occurs and results in a second crystal structure.

Among other things, piezoelectric materials and methods of their manufacture are described; particularly methods of forming regions of varying crystal structure within a relaxor piezoelectric substrate. Such methods may including heating the piezoelectric substrate above the transition temperature and below the Curie temperature such that a first phase transition occurs to a first crystal structure; rapidly cooling the piezoelectric substrate below the transition temperature at a cooling rate that is sufficiently high for the first crystal structure to persist; and applying an electric field through one or more selected regions of the piezoelectric substrate, such that within the one or more selected regions, a second phase transition occurs and results in a second crystal structure.

A piezoelectric monocrystalline substrate is composed of a material represented by LiAO.sub.3 (A represents at least one element selected from the group consisting of niobium and tantalum), a bonding layer is compose of a material of an oxide of at least one element selected from the group consisting of niobium and tantalum, and an interface layer is provided along an interface between the piezoelectric monocrystalline substrate 6 and bonding layer, and the interface layer has a composition of E.sub.xO.sub.(1-x) (E represents at least one element selected from the group consisting of niobium and tantalum and 0.29≤x≤0.89).

A piezoelectric monocrystalline substrate is composed of a material represented by LiAO.sub.3 (A represents at least one element selected from the group consisting of niobium and tantalum), a bonding layer is compose of a material of an oxide of at least one element selected from the group consisting of niobium and tantalum, and an interface layer is provided along an interface between the piezoelectric monocrystalline substrate 6 and bonding layer, and the interface layer has a composition of E.sub.xO.sub.(1-x) (E represents at least one element selected from the group consisting of niobium and tantalum and 0.29≤x≤0.89).