A method is disclosed involving depositing a neutral orientation template layer onto a substrate after formation of chemical epitaxy or graphoepitaxy features on the substrate, but before deposition and orientation of a self-assemblable polymer. The orientation layer is arranged to bond with the substrate but not with certain features, so that it may be easily removed by vacuum or rinsing with organic solvent. The neutral orientation layer has a chemical affinity to match that of blocks in the self-assemblable polymer so that blocks of differing types wet the neutral orientation layer so that domains in the self-assembled polymer may lie side by side along the substrate surface, with interfaces normal to the substrate surface. The resulting aligned and oriented self-assembled polymer may itself be used as a resist for device lithography of the substrate.

A method is disclosed involving depositing a neutral orientation template layer onto a substrate after formation of chemical epitaxy or graphoepitaxy features on the substrate, but before deposition and orientation of a self-assemblable polymer. The orientation layer is arranged to bond with the substrate but not with certain features, so that it may be easily removed by vacuum or rinsing with organic solvent. The neutral orientation layer has a chemical affinity to match that of blocks in the self-assemblable polymer so that blocks of differing types wet the neutral orientation layer so that domains in the self-assembled polymer may lie side by side along the substrate surface, with interfaces normal to the substrate surface. The resulting aligned and oriented self-assembled polymer may itself be used as a resist for device lithography of the substrate.

A semiconductor wafer forms on a mold containing a dopant. The dopant dopes a melt region adjacent the mold. There, dopant concentration is higher than in the melt bulk. A wafer starts solidifying. Dopant diffuses poorly in solid semiconductor. After a wafer starts solidifying, dopant can not enter the melt. Afterwards, the concentration of dopant in the melt adjacent the wafer surface is less than what was present where the wafer began to form. New wafer regions grow from a melt region whose dopant concentration lessens over time. This establishes a dopant gradient in the wafer, with higher concentration adjacent the mold. The gradient can be tailored. A gradient gives rise to a field that can function as a drift or back surface field. Solar collectors can have open grid conductors and better optical reflectors on the back surface, made possible by the intrinsic back surface field.

In a first step, protrusions (42) are formed on a surface of an SiC substrate (40), and the SiC substrate (40) is etched. In a second step, the protrusions (42) of the SiC substrate (40) are epitaxially grown through MSE process, and an epitaxial layer (43a) containing threading screw dislocation, which has been largely grown in the vertical (c-axis) direction as a result of MSE process, is at least partially removed. In a third step, MSE process is performed again on the SiC substrate (40) after the second step, to cause epitaxial layers (43) containing no threading screw dislocation to be grown in the horizontal (a-axis) direction to be connected at the molecular level, so that one monocrystalline 4HSiC semiconductor wafer (45) having a large area is generated throughout an Si-face or a C-face of the SiC substrate (40).

In a first step, protrusions (42) are formed on a surface of an SiC substrate (40), and the SiC substrate (40) is etched. In a second step, the protrusions (42) of the SiC substrate (40) are epitaxially grown through MSE process, and an epitaxial layer (43a) containing threading screw dislocation, which has been largely grown in the vertical (c-axis) direction as a result of MSE process, is at least partially removed. In a third step, MSE process is performed again on the SiC substrate (40) after the second step, to cause epitaxial layers (43) containing no threading screw dislocation to be grown in the horizontal (a-axis) direction to be connected at the molecular level, so that one monocrystalline 4HSiC semiconductor wafer (45) having a large area is generated throughout an Si-face or a C-face of the SiC substrate (40).

A self-aligned tunable metamaterial is formed as a wire mesh. Self-aligned channel grids are formed in layers in a silicon substrate using deep trench formation and a high-temperature anneal. Vertical wells at the channels may also be etched. This may result in a three-dimensional mesh grid of metal and other material. In another embodiment, metallic beads are deposited at each intersection of the mesh grid, the grid is encased in a rigid medium, and the mesh grid is removed to form an artificial nanocrystal.

A self-aligned tunable metamaterial is formed as a wire mesh. Self-aligned channel grids are formed in layers in a silicon substrate using deep trench formation and a high-temperature anneal. Vertical wells at the channels may also be etched. This may result in a three-dimensional mesh grid of metal and other material. In another embodiment, metallic beads are deposited at each intersection of the mesh grid, the grid is encased in a rigid medium, and the mesh grid is removed to form an artificial nanocrystal.

A crystal substrate 1 includes an underlying layer 2 and a thick film 3. The underlying layer 2 is composed of a crystal of a nitride of a group 13 element and includes a first main face 2a and a second main face 2b. The thick film 3 is composed of a crystal of a nitride of a group 13 element and provided over the first main face of the underlying layer. The underlying layer 2 includes a low carrier concentration region 5 and a high carrier concentration region 4 both extending between the first main face 2a and the second main face 2b. The low carrier concentration region 5 has a carrier concentration of 10.sup.17/cm.sup.3 or lower and a defect density of 10.sup.7/cm.sup.2 or lower. The high carrier concentration region 4 has a carrier concentration of 10.sup.19/cm.sup.3 or higher and a defect density of 10.sup.8/cm.sup.2 or higher. The thick film 3 has a carrier concentration of 10.sup.18/cm.sup.3 or higher and 10.sup.19/cm.sup.3 or lower and a defect density of 10.sup.7/cm.sup.2 or lower.

Growth of single crystal epitaxial films of the perovskite crystal structure by liquid- or vapor-phase means can be accomplished by providing single-crystal perovskite substrate materials of improved lattice parameter match in the lattice parameter range of interest. Current substrates do not provide as good a lattice match, have inferior properties, or are of limited size and availability because cost of materials and difficulty of growth. This problem is solved by the single-crystal perovskite solid solutions described herein grown from mixtures with an indifferent melting point that occurs at a congruently melting composition at a temperature minimum in the melting curve in the pseudo-binary molar phase diagram. Accordingly, single-crystal perovskite solid solutions, structures, and devices including single-crystal perovskite solid solutions, and methods of making single-crystal perovskite solid solutions are described herein.

Growth of single crystal epitaxial films of the perovskite crystal structure by liquid- or vapor-phase means can be accomplished by providing single-crystal perovskite substrate materials of improved lattice parameter match in the lattice parameter range of interest. Current substrates do not provide as good a lattice match, have inferior properties, or are of limited size and availability because cost of materials and difficulty of growth. This problem is solved by the single-crystal perovskite solid solutions described herein grown from mixtures with an indifferent melting point that occurs at a congruently melting composition at a temperature minimum in the melting curve in the pseudo-binary molar phase diagram. Accordingly, single-crystal perovskite solid solutions, structures, and devices including single-crystal perovskite solid solutions, and methods of making single-crystal perovskite solid solutions are described herein.