A neutron imaging system, including: a plurality of Li-III-VI.sub.2 semiconductor crystals arranged in an array, wherein III represents a Group III element and VI represents a Group VI element; and electronics operable for detecting and a charge in each of the plurality of crystals in the presence of neutrons and for imaging the neutrons. Each of the crystals is formed by: melting the Group III element; adding the Li to the melted Group III element at a rate that allows the Li and Group III element to react, thereby providing a single phase Li-III compound; and adding the Group VI element to the single phase Li-III compound and heating. Optionally, each of the crystals is also formed by doping with a Group IV element activator.

A neutron imaging system, including: a plurality of Li-III-VI.sub.2 semiconductor crystals arranged in an array, wherein III represents a Group III element and VI represents a Group VI element; and electronics operable for detecting and a charge in each of the plurality of crystals in the presence of neutrons and for imaging the neutrons. Each of the crystals is formed by: melting the Group III element; adding the Li to the melted Group III element at a rate that allows the Li and Group III element to react, thereby providing a single phase Li-III compound; and adding the Group VI element to the single phase Li-III compound and heating. Optionally, each of the crystals is also formed by doping with a Group IV element activator.

A photodetector device, including: a scintillator material operable for receiving incident radiation and emitting photons in response; a photodetector material coupled to the scintillator material operable for receiving the photons emitted by the scintillator material and generating a current in response, wherein the photodetector material includes a chalcopyrite semiconductor crystal; and a circuit coupled to the photodetector material operable for characterizing the incident radiation based on the current generated by the photodetector material. Optionally, the scintillator material includes a gamma scintillator material and the incident radiation received includes gamma rays. Optionally, the photodetector material is further operable for receiving thermal neutrons and generating a current in response. The circuit is further operable for characterizing the thermal neutrons based on the current generated by the photodetector material.

A photodetector device, including: a scintillator material operable for receiving incident radiation and emitting photons in response; a photodetector material coupled to the scintillator material operable for receiving the photons emitted by the scintillator material and generating a current in response, wherein the photodetector material includes a chalcopyrite semiconductor crystal; and a circuit coupled to the photodetector material operable for characterizing the incident radiation based on the current generated by the photodetector material. Optionally, the scintillator material includes a gamma scintillator material and the incident radiation received includes gamma rays. Optionally, the photodetector material is further operable for receiving thermal neutrons and generating a current in response. The circuit is further operable for characterizing the thermal neutrons based on the current generated by the photodetector material.

Casting polycrystalline silicon includes placing a bottomless cooling crucible divided at least partially in the axis direction into a plurality of parts in the peripheral direction and having an inner surface coated with a release agent containing nitrogen, in an induction coil of a chamber charged with an inert gas; melting a raw material of polycrystalline silicon in the bottomless cooling crucible by electromagnetic induction heating using the induction coil; and pulling out the molten silicon downward while cooling and solidifying it. Pullout of the solidified molten silicon is performed through adjusting the carbon concentration of the molten silicon to 4.010.sup.17 atoms/cm.sup.3 or more to 6.010.sup.17 atoms/cm.sup.3 or less, the oxygen concentration thereof to 0.310.sup.17 atoms/cm.sup.3 or more to 5.010.sup.17 atoms/cm.sup.3 or less, and the nitrogen concentration to 8.010.sup.13 atoms/cm.sup.3 or more to 1.010.sup.18 atoms/cm.sup.3 or less.

A method comprising introducing a first casting material into a casting mold; applying directional solidification to the first casting material in the casting mold; introducing a second casting material into the casting mold, the second casting material having a different chemical composition than the first casting material; applying directional solidification to the second casting material in the casting mold; and forming a molded article, wherein the molded article comprises a first region

A semiconductor compound injection synthesis method relating to the synthesis of semiconductor materials, being implemented on the basis of a synthesis system. The synthesis system adopts an open gas source device. The method includes: placing materials, probing the open gas source device, melting metal materials, and gasifying the gas source material to complete the synthesis. Beneficial effects: in the synthesis method of the present invention, the lower part of the baffle of the open gas source device is a reaction chamber. During the synthesis, the contact area between the gas source material and the melt is at least 22 times the contact area of the traditional double-tube method. In the present invention, there is no isolation of the covering agent in the reaction chamber, and the two reaction elements are always in contact at the liquid surface. In a specific implementation case, when the method of the present invention is used to synthesize phosphating steel materials, compared with the traditional double-tube injection method, the efficiency of the method is improved by 12 times.

A device and method for centrifugally synthesizing and growing a compound crystal, which relate to the field of preparation of compound semiconductors. The device comprises a furnace body and a crucible in the furnace body, wherein a sealing groove is formed in the top of the crucible, a sealing cover matching the sealing groove is provided, and the crucible is connected to a centrifugal electric motor outside the furnace body by means of a crucible rod. The method comprises the steps of placing a raw material, assembling the device, sealing the crucible, performing centrifugal synthesis, and growing a crystal.