An embodiment comprises: a chamber; a crucible provided in the chamber and accommodating a molten liquid which is a raw material for single crystal growth; a crucible screen disposed on the upper end of the crucible; and a moving unit for raising or lowering the crucible screen, wherein the crucible screen and a first upper adiabatic unit are raised to control the stroke distance, thereby preventing the impossibility of a lift-off process caused by a shortage of the stroke distance and the generation of cracks in single crystals.

A poly-crystalline silicon ingot having a bottom and defining a vertical direction includes a plurality of silicon grains grown in the vertical direction, in which the plurality of the silicon grains have at least three crystal orientations; and a nucleation promotion layer comprising a plurality of chips and chunks of poly-crystalline silicon on the bottom, wherein the poly-crystalline silicon ingot has a defect density at a height ranging from about 150 mm to about 250 mm of the poly-crystalline silicon ingot that is less than 15%.

An apparatus may include a crucible configured to contain the melt, the melt having an exposed surface separated from a floor of the crucible by a first distance, a housing comprising a material that is non-contaminating to the melt, the housing comprising a plurality of sidewalls and a top that are configured to contact the melt, and a plurality of heating elements isolated from the melt and disposed along a transverse direction perpendicular to a pulling direction of the crystalline sheet, the plurality of heating elements being individually powered, wherein the plurality of heating elements are disposed at a second set of distances from the exposed surface of the melt that are less than the first distance, and wherein the plurality of heating elements are configured to vary a heat flux profile along the transverse direction when power is supplied individually to the plurality of heating elements.

An additive manufacturing system utilizing an epitaxy process, and method of manufacture, utilizes a heating source and a cooling source to control thermal gradients and a solidification rate of each slice of a workpiece manufactured from a seed having a directional grain microstructure. An energy gun is utilized to melt selected regions of each successive layer of a plurality layers of a powder in a powder bed to successively form each solidified slice of the workpiece.

The present invention relates to a scintillator, a method for manufacturing the same, and an application for the same. The scintillator according to an embodiment of the present invention includes a matrix material including, as a main component, thallium, lanthanum, and a halogen element; and an activator doped onto the matrix material. The scintillator according to an embodiment of the present invention has a formula TlaLabXc:yCe, and in the formula: X is a halogen element; a=1, b=2, c=7, or a=2, b=1, c=5, or a=3, b=1, c=6; and y>0 and y0.5. The scintillator according to an embodiment of the present invention has a high efficiency of detecting radiations, a greater light yield, and an excellent fluorescence decay time characteristic.

A method for manufacturing a polycrystalline silicon ingot includes steps of: a) melting a silicon material in a container disposed in a thermal field to form a molten silicon; b) controlling the thermal field to provide heat to the molten silicon from above the container and to solidify a portion of the molten silicon contacting a base part and at least a portion of a wall part proximate to the base part of the container to form a solid silicon crystalline isolation layer; and c) controlling the thermal field to continuously provide heat to the rest of the molten silicon from above the container and to solidify the rest of the molten silicon gradually from a bottom to a top of the rest of the molten silicon to form a polycrystalline silicon ingot.

Methods and wafers for low etch pit density, low slip line density, and low strain indium phosphide are disclosed and may include an indium phosphide single crystal wafer having a diameter of 4 inches or greater, having a measured etch pit density of less than 500 cm.sup.?2, and having fewer than 5 dislocations or slip lines as measured by x-ray diffraction imaging. The wafer may have a measured etch pit density of 200 cm.sup.?2 or less, or 100 cm.sup.?2 or less, or 10 cm.sup.?2 or less. The wafer may have a diameter of 6 inches or greater. An area of the wafer with a measured etch pit density of zero may at least 80% of the total area of the surface. An area of the wafer with a measured etch pit density of zero may be at least 90% of the total area of the surface.

Methods and systems for low etch pit density 6 inch semi-insulating gallium arsenide wafers may include a semi-insulating gallium arsenide single crystal wafer having a diameter of 6 inches or greater without intentional dopants for reducing dislocation density, an etch pit density of less than 1000 cm.sup.2, and a resistivity of 110.sup.7 -cm or more. The wafer may have an optical absorption of less than 5 cm.sup.1 less than 4 cm.sup.1 or less than 3 cm.sup.1 at 940 nm wavelength. The wafer may have a carrier mobility of 3000 cm.sup.2/V-sec or higher. The wafer may have a thickness of 500 m or greater. Electronic devices may be formed on a first surface of the wafer. The wafer may have a carrier concentration of 1.110.sup.7 cm.sup.3 or less.

The invention discloses a device and a method for continuous VGF crystal growth through reverse injection synthesis, relating to a device for preparing a semiconductor crystal and growing a single crystal, in particular to a method and a device for continuously growing the crystal in situ by using a VGF method and reverse injection synthesis. The device includes a furnace body, a crucible, a heat preservation system, a heating system, a temperature control system and a gas pressure regulation system, wherein the crucible is arranged in the furnace body, has a synthesis unit at its upper part, and has a crystal growth unit and a seed crystal unit at its lower part, and the synthesis unit is communicated with the crystal growth unit through capillary pores.

Provided are a P-type ZrCoSb-based half-Heusler single crystal alloy and a preparation method thereof. The method for preparing the P-type ZrCoSb-based half-Heusler single crystal alloy includes: subjecting alloy raw materials to smelting under a first protective atmosphere to obtain a half-Heusler polycrystalline alloy ingot, the alloy raw materials corresponding to a chemical composition of the P-type ZrCoSb-based half-Heusler single crystal alloy; and subjecting the half-Heusler polycrystalline alloy ingot to vertical Bridgman directional crystallization under a second protective atmosphere to obtain the P-type ZrCoSb-based half-Heusler single crystal alloy. The P-type ZrCoSb-based half-Heusler single crystal alloy has the chemical composition of ZrCoSb.sub.1-xSn.sub.x, x in the ZrCoSb.sub.1-xSn.sub.x being in a range of 0.1x0.3; and the P-type ZrCoSb-based half-Heusler single crystal alloy has an MgAgAs-type crystal structure.