A method of preparation of semiconductor material. The method includes: adding an organic substance containing a benzene ring and dodecacalcium hepta-aluminate (12CaO.7Al.sub.2O.sub.3 or C12A7) to a test tube, and sealing the test tube; heating the test tube to a temperature of 200-300 C., and holding the temperature for 1 to 3 hours; and continuously heating the test tube to a temperature of 900-1300 C., and holding the temperature for 10-120 hours.

A polycrystalline silicon ingot having a value of T.sub.eT.sub.s, T, of 50 C. or less, wherein T.sub.s and T.sub.e are the onset temperature and the completion temperature of melting, respectively, when the temperature is increased at a rate of 60 C./minute or less in the temperature range of 1400 C. or more is used as the production raw material for single crystal silicon. The present invention provides a polycrystalline silicon ingot or polycrystalline silicon rod suitable for stably producing single crystal silicon.

A polycrystalline silicon ingot having a value of T.sub.eT.sub.s, T, of 50 C. or less, wherein T.sub.s and T.sub.e are the onset temperature and the completion temperature of melting, respectively, when the temperature is increased at a rate of 60 C./minute or less in the temperature range of 1400 C. or more is used as the production raw material for single crystal silicon. The present invention provides a polycrystalline silicon ingot or polycrystalline silicon rod suitable for stably producing single crystal silicon.

An ingot includes a first surface, a second surface opposite to the first surface, and a third surface positioned along a first direction and connecting the first surface and the second surface. The ingot includes: a first pseudo single crystal region; an intermediate region containing one or more pseudo single crystal regions; and a second pseudo single crystal region. The first pseudo single crystal region, the intermediate region, and the second pseudo single crystal region are positioned adjacent sequentially in a second direction perpendicular to the first direction. In the second direction, a width of each of the first and second pseudo single crystal regions is larger than a width of the first intermediate region. Each of a boundary between the first pseudo single crystal region and the intermediate region and a boundary between the second pseudo single crystal region and the intermediate region includes a coincidence boundary.

An ingot includes a first surface, a second surface opposite to the first surface, and a third surface positioned along a first direction and connecting the first surface and the second surface. The ingot includes: a first pseudo single crystal region; an intermediate region containing one or more pseudo single crystal regions; and a second pseudo single crystal region. The first pseudo single crystal region, the intermediate region, and the second pseudo single crystal region are positioned adjacent sequentially in a second direction perpendicular to the first direction. In the second direction, a width of each of the first and second pseudo single crystal regions is larger than a width of the first intermediate region. Each of a boundary between the first pseudo single crystal region and the intermediate region and a boundary between the second pseudo single crystal region and the intermediate region includes a coincidence boundary.

A method of preparation of semiconductor material. The method includes: adding an organic substance containing a benzene ring and dodecacalcium hepta-aluminate (12CaO.7Al.sub.2O.sub.3 or C12A7) to a test tube, and sealing the test tube; heating the test tube to a temperature of 200-300 C., and holding the temperature for 1 to 3 hours; and continuously heating the test tube to a temperature of 900-1300 C., and holding the temperature for 10-120 hours.

A method of preparation of semiconductor material. The method includes: adding an organic substance containing a benzene ring and dodecacalcium hepta-aluminate (12CaO.7Al.sub.2O.sub.3 or C12A7) to a test tube, and sealing the test tube; heating the test tube to a temperature of 200-300 C., and holding the temperature for 1 to 3 hours; and continuously heating the test tube to a temperature of 900-1300 C., and holding the temperature for 10-120 hours.

A Group VB element doped with a -gallium oxide crystalline material, and a preparation method and application thereof. The series doped with the Ga.sub.2O.sub.3 crystalline material is monoclinic, the space group is C2/m, the resistivity is in the range of 2.010.sup.4 to 110.sup.4.Math.cm, and/or the carrier concentration is in the range of 510.sup.12 to 710.sup.20/cm.sup.3. The preparation method comprises steps of: mixing M.sub.2O.sub.5 and Ga.sub.2O.sub.3 with a purity of 4N or more at molar ratio of (0.000000001-0.01):(0.999999999-0.99); an then performing crystal growth. The present invention can prepare a high-conductivity -Ga.sub.2O.sub.3 crystalline material with n-type conductivity characteristics by conventional processes, providing a basis for applications thereof to electrically powered electronic devices, optoelectronic devices, photocatalysts or conductive substrates.

A transparent complex oxide sintered body is manufactured by sintering a compact in an inert atmosphere or vacuum, and HIP treating the sintered compact, provided that the compact is molded from a source powder based on a rare earth oxide: (Tb.sub.xY.sub.1-x).sub.2O.sub.3 wherein 0.4x0.6, and the compact, when heated in air from room temperature at a heating rate of 15 C./min, exhibits a weight gain of at least y% due to oxidative reaction, y being determined by the formula: y=2x+0.3. The sintered body has a long luminescent lifetime as a result of controlling the valence of Tb ion.

A transparent complex oxide sintered body is manufactured by sintering a compact in an inert atmosphere or vacuum, and HIP treating the sintered compact, provided that the compact is molded from a source powder based on a rare earth oxide: (Tb.sub.xY.sub.1-x).sub.2O.sub.3 wherein 0.4x0.6, and the compact, when heated in air from room temperature at a heating rate of 15 C./min, exhibits a weight gain of at least y% due to oxidative reaction, y being determined by the formula: y=2x+0.3. The sintered body has a long luminescent lifetime as a result of controlling the valence of Tb ion.