An apparatus for producing an SiC single crystal includes a crucible for accommodating an Si—C solution and a seed shaft having a lower end surface where an SiC seed crystal (36) would be attached. The seed shaft includes an inner pipe that extends in a height direction of the crucible and has a first passage. An outer pipe accommodates the inner pipe and constitutes a second passage between itself and the inner pipe and has a bottom portion whose lower end surface covers a lower end opening of the outer pipe. One passage of the first and second passages serves as an introduction passage where coolant gas flows downward, and the other passage serves as a discharge passage where coolant gas flows upward. A region inside the pipe that constitutes the introduction passage is to be overlapped by a region of not less than 60% of the SiC seed crystal.

The present invention relates to an apparatus and method for directional solidification of silicon. The apparatus can use a cooling platform to cool a portion of a bottom of a directional solidification crucible. The apparatus and method of the present invention can be used to make silicon crystals for use in solar cells.

A method for producing the growth of a semiconductor material, in particular of type II-VI, uses a melt of the semiconductor placed in a sealed bulb under vacuum or under controlled atmosphere, the bulb being subjected to a sufficient temperature gradient for first maintaining the melt in the liquid state, then causing its progressive crystallization from the surface towards the bottom. The method further comprises an element capable of floating on the surface of the melt, and equipped with a substantially central bore, intended for receiving a seed crystal for permitting the nucleation leading to the preparation of a seed crystal, and also supporting the seed crystal above the melt while maintaining it in contact with the melt in order to permit the continued crystallization from the seed crystal by lowering the temperature gradient.

A TiAl intermetallic compound single crystal material and a preparation method therefor are disclosed. The alloy composition of the material comprises Ti.sub.aAl.sub.bNb.sub.c(C, Si).sub.d, wherein 43≦b≦49, 2≦c≦10, a+b+c=100, and 0≦d≦1 (at. %).

Methods and devices for detecting incident radiation are provided. The methods and devices use high quality single-crystals of photoactive semiconductor compounds in combination with metal anodes and metal cathodes that provide for enhanced photodetector performance.

The present disclosure discloses a shell mold chamber, a foundry furnace and a method for casting single crystal, fine crystal and non-crystal, which employ the technique of asynchronous-curving supercooling, and belongs to the technical field of precise casting apparatuses. Such a three-function foundry furnace includes a heating coil winding, a first thermal-shield assembly, a first superconducting coil, a second thermal-shield assembly and a second superconducting coil; and the first superconducting coil is provided at an inside of the first thermal-shield assembly, and the second superconducting coil is provided at an inside of the second thermal-shield assembly; and directions of a magnetic field generated by the first superconducting coil and a magnetic field generated by the second superconducting coil are opposite; and the first superconducting coil and the heating coil winding form a forward-directional static-magnetic-field heating zone, and the second superconducting coil forms a reverse-directional static-magnetic-field zone.

A single-crystal production equipment which includes, at least: a raw material supply apparatus which supplies a granular raw material to a melting apparatus positioned therebelow; the melting apparatus heats and melts the granular raw material to generate a raw material melt and supplies the raw material melt into a single-crystal production crucible positioned therebelow; and a crystallization apparatus which includes the single-crystal production crucible in which a seed single crystal is placed on the bottom, and a first infrared ray irradiation equipment which irradiates an infrared ray to the upper surface of the seed single crystal in the single-crystal production crucible, and the single-crystal production equipment is configured such that the raw material melt is dropped into a melt formed by irradiating the upper surface of the seed single crystal with the infrared ray, and a single crystal is allowed to precipitate out of the thus formed mixed melt.

In a crystal growth furnace having an array of vertically arranged heaters to provide controlled heating zones within a chamber, and a crucible for holding crystal material, wherein the crystal is grown vertically through the heating zones, the improvement includes a laser mounted outside the chamber which radiates a beam of energy to locally melt precipitates and inclusions. The furnace includes a mechanism to position the laser vertically to, at or near the interface between the formed crystal and crystal melt material above the formed crystal. The crystal material can be CdZnTe.

The gallium arsenide single crystal substrate has a circular main surface, and when the diameter of the main surface of the gallium arsenide single crystal substrate is represented by D and the number of etch pits formed on the main surface by immersing the gallium arsenide single crystal substrate in molten potassium hydroxide at 500° C. for 10 minutes is counted, the number C.sub.1 of etch pits in a first circular region having a diameter of 0.2D around the center of the main surface is 0 or more and 10 or less.

A heat exchange device for a single crystal furnace is provided, including a heat exchanger on which an inner chamber for heat exchange defined in a shape of circular truncated cone is formed. A convex portion is defined by a chamber wall of the inner chamber for heat exchange partially projecting along a radial direction of the inner chamber for heat exchange, the convex portion extends along a direction of an axis of the inner chamber for heat exchange, and a minimum distance between an end away from the chamber wall of the inner chamber for heat exchange of the convex portion and the axis of the inner chamber for heat exchange is denoted as L, which is greater than or equal to a minimum radius of a cross section of the inner chamber for heat exchange.