Abstract: An original wafer, typically silicon, has the form of a desired end PV wafer. The original may be made by rapid solidification or CVD. It has small grains. It is encapsulated in a clean thin film, which contains and protects the silicon when recrystallized to create a larger grain structure. The capsule can be made by heating a wafer in the presence of oxygen, or steam, resulting in silicon dioxide on the outer surface, typically 1-2 microns. At least one support element supports the wafer at the time the capsule is provided and blocks only minimal surface area from contact with the film forming atmosphere. There may be a plurality of support elements, or a surface may provide such support. The capsule contains the molten material during recrystallization, and protects against impurities. Recrystallization may be in air. After recrystallization, the capsule is removed.

Abstract: An original wafer, typically silicon, has the form of a desired end PV wafer. The original may be made by rapid solidification or CVD. It has small grains. It is encapsulated in a clean thin film, which contains and protects the silicon when recrystallized to create a larger grain structure. The capsule can be made by heating a wafer in the presence of oxygen, or steam, resulting in silicon dioxide on the outer surface, typically 1-2 microns. At least one support element supports the wafer at the time the capsule is provided and blocks only minimal surface area from contact with the film forming atmosphere. There may be a plurality of support elements, or a surface may provide such support. The capsule contains the molten material during recrystallization, and protects against impurities. Recrystallization may be in air. After recrystallization, the capsule is removed.

Abstract: An original wafer, typically silicon, has the form of a desired end PV wafer. The original may be made by rapid solidification or CVD. It has small grains. It is encapsulated in a clean thin film, which contains and protects the silicon when recrystallized to create a larger grain structure. The capsule can be made by heating a wafer in the presence of oxygen, or steam, resulting in silicon dioxide on the outer surface, typically 1-2 microns. Further heating creates a molten zone in space, through which the wafer travels, resulting in recrystallization with a larger grain size. The capsule contains the molten material during recrystallization, and protects against impurities. Recrystallization may be in air. Thermal transfer through backing plates minimizes stresses and defects. After recrystallization, the capsule is removed.

Abstract: Methods of manufacturing an article use three-dimensional printing for a portion of the manufacturing. Three-dimensionally printing is conducted onto a powder bed which contains both organic-solvent-soluble, water-insoluble particles and water soluble, organic-solvent-insoluble particles. The water-soluble particles which may be selected for properties such as size and may include more than one substance. The organic-solvent-insoluble particles may further include at least one substantially insoluble substance such as a member of the calcium phosphate family. Printing may be done using an aqueous binder liquid. After removal of unbound powder, the preform may be exposed to the vapor of an organic solvent which causes the particles of organic-soluble-polymer to fuse to each other. This may further be followed by dissolving out the water-soluble particles, if such particles were present in the powder.

Abstract: An original wafer, typically silicon, has the form of a desired end PV wafer. The original may be made by rapid solidification or CVD. It has small grains. It is encapsulated in a clean thin film, which contains and protects the silicon when recrystallized to create a larger grain structure. The capsule can be made by heating a wafer in the presence of oxygen, or steam, resulting in silicon dioxide on the outer surface, typically 1-2 microns. Further heating creates a molten zone in space, through which the wafer travels, resulting in recrystallization with a larger grain size. The capsule contains the molten material during recrystallization, and protects against impurities. Recrystallization may be in air. Thermal transfer through backing plates minimizes stresses and defects. After recrystallization, the capsule is removed.

Abstract: Methods of manufacturing an article use three-dimensional printing for a portion of the manufacturing. Three-dimensionally printing is conducted onto a powder bed which contains both organic-solvent-soluble, water-insoluble particles and water soluble, organic-solvent-insoluble particles. The water-soluble particles which may be selected for properties such as size and may include more than one substance. The organic-solvent-insoluble particles may further include at least one substantially insoluble substance such as a member of the calcium phosphate family. Printing may be done using an aqueous binder liquid. After removal of unbound powder, the preform may be exposed to the vapor of an organic solvent which causes the particles of organic-soluble-polymer to fuse to each other. This may further be followed by dissolving out the water-soluble particles, if such particles were present in the powder.

Abstract: A drop on demand printer has a nozzle with an orifice and a surrounding annular land. Surrounding the land is an edge, which is surrounded by a perimetrical surface that is inclined to the land at an angle ?. A pressure controller maintains a positive overpressure on liquid to be printed such that a cap of liquid is substantially always present covering the orifice and the land. The edge between the land and the perimetrical surface prevents liquid from overflowing, and maintains the cap, if the pressure is maintained between lower and upper limits disclosed. The liquid to be printed preferably wets the orifice land, which may be alumina, glass, ceramic, and others. Liquids with very small, even zero, wetting angles relative to the land may be used, such as water and organic solvents, including, isopropyl and ethyl alcohol and chloroform. The liquid can be loaded with dissolved polymers, or particles, such as of polymer or ceramic.

Abstract: A drop on demand printer has a nozzle with an orifice and a surrounding annular land. Surrounding the land is an edge, which is surrounded by a perimetrical surface that is inclined to the land at an angle &agr;. A pressure controller maintains a positive overpressure on liquid to be printed such that a cap of liquid is substantially always present covering the orifice and the land. The edge between the land and the perimetrical surface prevents liquid from overflowing, and maintains the cap, if the pressure is maintained between lower and upper limits disclosed. The liquid to be printed preferably wets the orifice land, which may be alumina, glass, ceramic, and others. Liquids with very small, even zero, wetting angles relative to the land may be used, such as water and organic solvents, including, isopropyl and ethyl alcohol and chloroform. The liquid can be loaded with dissolved polymers, or particles, such as of polymer or ceramic.

Abstract: A powder bed (32) is built up by repeated deposition of a slurry that contains powder. Layers are made by depositing a liquid dispersion of the desired powdered material, which then slip-casts into the forming powder bed to make a new layer (34). The slurry may be deposited in any suitable manner, such as by raster or vector scanning, or by a plurality of simultaneous jets that coalesce before the liquid slip-casts into the bed, or by individual drops, the deposits of which are individually controlled, thereby generating a regular surface for each layer.

Abstract: A droplet generator and ink jet printhead assembly employing the droplet generator are disclosed. The droplet generator can operate with a wide range of fluids over a wide range of conditions, is easily serviced, and can be easily integrated into a machine such as a Three Dimensional Printing machine. The assembly includes a nozzle having an orifice, a liquid reservoir or supply for containing a liquid to be emitted from the nozzle and a non-resonant elastically deformable fluid conduit for conveying the liquid from the liquid reservoir to the nozzle. A transducer is disposed in abutting relation with the fluid conduit a predetermined distance from the nozzle. The transducer is energized by a suitable electrical signal, such as a sinusoidal signal. The transducer causes compression of the conduit and provides a wave which propagates along the fluid conduit and fluid contained therein toward the nozzle and orifice.