In the present invention, in producing a SiC single crystal in accordance with a solution method, a crucible containing SiC as a main component and having an oxygen content of 100 ppm or less is used as the crucible to be used as a container for a SiC solution. In another embodiment, a sintered body containing SiC as a main component and having an oxygen content of 100 ppm or less is placed in the crucible to be used as a container for a SiC solution. The SiC crucible and SiC sintered body are obtained by molding and baking a SiC raw-material powder having an oxygen content of 2000 ppm or less. SiC, which is the main component of these, serves as a source for Si and C and allows Si and C to elute into the SiC solution by heating.

The present disclosure relates to a process for fabricating a crystalline scintillator material with a structure of elpasolite type of theoretical composition A.sub.2BC.sub.(1-y)M.sub.yX.sub.(6-y) wherein: A is chosen from among Cs, Rb, K, Na, B is chosen from among Li, K, Na, C is chosen from among the rare earths, Al, Ga, M is chosen from among the alkaline earths, X is chosen from among F, Cl, Br, I,

y representing the atomic fraction of substitution of C by M and being in the range extending from 0 to 0.05, comprising its crystallization by cooling from a melt bath comprising r moles of A and s moles of B, the melt bath in contact with the material containing A and B in such a way that 2s/r is above 1. The process shows an improved fabrication yield. Moreover, the crystals obtained can have compositions closer to stoichiometry and have improved scintillation properties.

The present disclosure relates to a process for fabricating a crystalline scintillator material with a structure of elpasolite type of theoretical composition A.sub.2BC.sub.(1-y)M.sub.yX.sub.(6-y) wherein: A is chosen from among Cs, Rb, K, Na, B is chosen from among Li, K, Na, C is chosen from among the rare earths, Al, Ga, M is chosen from among the alkaline earths, X is chosen from among F, Cl, Br, I,

y representing the atomic fraction of substitution of C by M and being in the range extending from 0 to 0.05, comprising its crystallization by cooling from a melt bath comprising r moles of A and s moles of B, the melt bath in contact with the material containing A and B in such a way that 2s/r is above 1. The process shows an improved fabrication yield. Moreover, the crystals obtained can have compositions closer to stoichiometry and have improved scintillation properties.

A scintillation crystal can include Ln.sub.(1-y)RE.sub.yX.sub.3, wherein Ln represents a rare earth element, RE represents a different rare earth element, y has a value in a range of 0 to 1, and X represents a halogen. In an embodiment, RE is Ce, and the scintillation crystal is doped with Sr, Ba, or a mixture thereof at a concentration of at least approximately 0.0002 wt. %. In another embodiment, the scintillation crystal can have unexpectedly improved linearity and unexpectedly improved energy resolution properties. In a further embodiment, a radiation detection system can include the scintillation crystal, a photosensor, and an electronics device. Such a radiation detection system can be useful in a variety of radiation imaging applications.

A scintillation crystal can include Ln.sub.(1-y)RE.sub.yX.sub.3, wherein Ln represents a rare earth element, RE represents a different rare earth element, y has a value in a range of 0 to 1, and X represents a halogen. In an embodiment, RE is Ce, and the scintillation crystal is doped with Sr, Ba, or a mixture thereof at a concentration of at least approximately 0.0002 wt. %. In another embodiment, the scintillation crystal can have unexpectedly improved linearity and unexpectedly improved energy resolution properties. In a further embodiment, a radiation detection system can include the scintillation crystal, a photosensor, and an electronics device. Such a radiation detection system can be useful in a variety of radiation imaging applications.

Device and method for immersed synthesis and continuous growth of phosphides under a magnetic field are disclosed in the field of semiconductor material preparation. In particular, device and method for synthesizing and growing semiconductor phosphides by means of immersing phosphorus into a metal melt under the action of a static magnetic field are disclosed. The device includes a furnace body, an injection synthesis system and a static magnetic field generator. The method includes A, heating the crucible to melt the metal and a covering material boron oxide in the crucible; B, immersing red phosphorus into the crucible; C, applying a static magnetic field surrounding the crucible, and adjusting the temperature gradient to start the synthesis; and D, performing crystal growth after completion of the synthesis. With the method provided by the present invention, the red phosphorus sinks into the melt in the form of a solid and floats upward from the bottom of the crucible after gasification, solving problems such as sucking-back generated by use of phosphorus bubbles; the transverse static magnetic field suppresses the bubble up-floating rate while suppressing the melt convection in the direction of the temperature gradient, so that the synthesis process is smoother and more rapid.

Device and method for immersed synthesis and continuous growth of phosphides under a magnetic field are disclosed in the field of semiconductor material preparation. In particular, device and method for synthesizing and growing semiconductor phosphides by means of immersing phosphorus into a metal melt under the action of a static magnetic field are disclosed. The device includes a furnace body, an injection synthesis system and a static magnetic field generator. The method includes A, heating the crucible to melt the metal and a covering material boron oxide in the crucible; B, immersing red phosphorus into the crucible; C, applying a static magnetic field surrounding the crucible, and adjusting the temperature gradient to start the synthesis; and D, performing crystal growth after completion of the synthesis. With the method provided by the present invention, the red phosphorus sinks into the melt in the form of a solid and floats upward from the bottom of the crucible after gasification, solving problems such as sucking-back generated by use of phosphorus bubbles; the transverse static magnetic field suppresses the bubble up-floating rate while suppressing the melt convection in the direction of the temperature gradient, so that the synthesis process is smoother and more rapid.

The present disclosure relates to a process for fabricating a crystalline scintillator material with a structure of elpasolite type of theoretical composition A.sub.2BC.sub.(1-y)M.sub.yX.sub.(6-y) wherein: A is chosen from among Cs, Rb, K, Na; B is chosen from among Li, K, Na; C is chosen from among the rare earths, Al, Ga; M is chosen from among the alkaline earths, X is chosen from among F, Cl, Br, I; y representing the atomic fraction of substitution of C by M and being in the range extending from 0 to 0.05, comprising its crystallization by cooling from a melt bath comprising r moles of A and s moles of B, the melt bath in contact with the material containing A and B in such a way that 2s/r is above 1. The process shows an improved fabrication yield. Moreover, the crystals obtained can have compositions closer to stoichiometry and have improved scintillation properties.

The present disclosure relates to a process for fabricating a crystalline scintillator material with a structure of elpasolite type of theoretical composition A.sub.2BC.sub.(1-y)M.sub.yX.sub.(6-y) wherein: A is chosen from among Cs, Rb, K, Na; B is chosen from among Li, K, Na; C is chosen from among the rare earths, Al, Ga; M is chosen from among the alkaline earths, X is chosen from among F, Cl, Br, I; y representing the atomic fraction of substitution of C by M and being in the range extending from 0 to 0.05, comprising its crystallization by cooling from a melt bath comprising r moles of A and s moles of B, the melt bath in contact with the material containing A and B in such a way that 2s/r is above 1. The process shows an improved fabrication yield. Moreover, the crystals obtained can have compositions closer to stoichiometry and have improved scintillation properties.

Provided is a GaAs wafer having suppressed carrier concentration and low dislocation density, as well as a large proportion of the area of a region with zero dislocation density to the GaAs wafer surface. The GaAs wafer has a silicon concentration of 1.010.sup.17 cm.sup.3 or more and less than 1.110.sup.18 cm.sup.3; an indium concentration of 3.010.sup.18 cm.sup.3 or more and less than 3.010.sup.19 cm.sup.3; a boron concentration of 2.510.sup.18 cm.sup.3 or more; a carrier concentration of 1.010.sup.16 cm.sup.3 or more and 4.010.sup.17 cm.sup.3 or less; and a proportion of the area of a region with zero dislocation density to the wafer surface of 91.0% or more.