The present invention provides a Ga-based van der Waals room-temperature ferromagnetic crystal material, preparation and use thereof, which belong to the technical field of nano magnetic material preparation. The materials include Fe.sub.3-aGa.sub.bTe.sub.2 (a=?0.3 to 0.1, b=0.8 to 1.2) and Fe.sub.5-c GeGa.sub.dTe.sub.2 (c=?0.2 to 0.2, d=0.01 to 0.5). The growth method of Fe.sub.3-aGa.sub.bTe.sub.2 (a=?0.3 to 0.1, b=0.8 to 1.2) is a self-flux method, using excess Ga and Te as flux to grow crystals. The growth method of Fe.sub.5-c GeGa.sub.dTe.sub.2 (c=?0.2 to 0.2, d=0.01 to 0.5) uses iodine as a transport agent to grow crystals. The Ga-based van der Waals room-temperature ferromagnetic crystal Fe.sub.3-a Ga.sub.bTe.sub.2 (a=?0.3 to 0.1, b=0.8 to 1.2) and Fe.sub.5-cGeGa.sub.dTe.sub.2 (c=?0.2 to 0.2, d=0.01 to 0.5) materials have Curie temperature of 330 K to 367 K and 320 K to 345 K, and the saturation magnetic moments are 50 emu/g to 57.2 emu/g and 80 emu/g to 88.5 emu/g, respectively.

The present invention provides a Ga-based van der Waals room-temperature ferromagnetic crystal material, preparation and use thereof, which belong to the technical field of nano magnetic material preparation. The materials include Fe.sub.3-aGa.sub.bTe.sub.2 (a=?0.3 to 0.1, b=0.8 to 1.2) and Fe.sub.5-c GeGa.sub.dTe.sub.2 (c=?0.2 to 0.2, d=0.01 to 0.5). The growth method of Fe.sub.3-aGa.sub.bTe.sub.2 (a=?0.3 to 0.1, b=0.8 to 1.2) is a self-flux method, using excess Ga and Te as flux to grow crystals. The growth method of Fe.sub.5-c GeGa.sub.dTe.sub.2 (c=?0.2 to 0.2, d=0.01 to 0.5) uses iodine as a transport agent to grow crystals. The Ga-based van der Waals room-temperature ferromagnetic crystal Fe.sub.3-a Ga.sub.bTe.sub.2 (a=?0.3 to 0.1, b=0.8 to 1.2) and Fe.sub.5-cGeGa.sub.dTe.sub.2 (c=?0.2 to 0.2, d=0.01 to 0.5) materials have Curie temperature of 330 K to 367 K and 320 K to 345 K, and the saturation magnetic moments are 50 emu/g to 57.2 emu/g and 80 emu/g to 88.5 emu/g, respectively.

Provided is a method that allows growing a single crystal of silicon carbide on an off-substrate of silicon carbide while suppressing surface roughening. The method for producing a crystal of silicon carbide includes rotating a seed crystal of silicon carbide while bringing the seed crystal into contact with a starting material solution containing silicon and carbon. A crystal growth surface of the seed crystal has an off-angle, and the position of a rotation center of the seed crystal lies downstream of the central position of the seed crystal in a step flow direction that is a formation direction of the off-angle.

An embodiment described herein includes a method for producing a wafer of a first semiconductor material. Said first semiconductor material has a first melting temperature. The method comprises providing a crystalline substrate of a second semiconductor material having a second melting temperature lower than the first melting temperature, and exposing the crystalline substrate to a flow of first material precursors for forming a first layer of the first material on the substrate. The method further comprising bringing the crystalline substrate to a first process temperature higher than the second melting temperature, and at the same time lower than the first melting temperature, in such a way the second material melts, separating the second melted material from the first layer, and exposing the first layer to the flow of the first material precursor for forming a second layer of the first material on the first layer.

An embodiment described herein includes a method for producing a wafer of a first semiconductor material. Said first semiconductor material has a first melting temperature. The method comprises providing a crystalline substrate of a second semiconductor material having a second melting temperature lower than the first melting temperature, and exposing the crystalline substrate to a flow of first material precursors for forming a first layer of the first material on the substrate. The method further comprising bringing the crystalline substrate to a first process temperature higher than the second melting temperature, and at the same time lower than the first melting temperature, in such a way the second material melts, separating the second melted material from the first layer, and exposing the first layer to the flow of the first material precursor for forming a second layer of the first material on the first layer.

Provided is a method for producing a SiC single crystal which can suppress generation of SiC polycrystals. The method according to the present embodiment is in accordance with a solution growth method. The method for producing a SiC single crystal according to the present embodiment comprises a power-output increasing step, a contact step, and a growth step. In the power-output increasing step, high-frequency power output of an induction heating device is increased to crystal-growth high-frequency power output. In the contact step, a SiC seed crystal is brought into contact with a SiC solution. The high-frequency power output of the induction heating device in the contact step is more than 80% of the crystal-growth high-frequency power output. The temperature of the SiC solution in the contact step is less than a crystal growth temperature. In the growth step, the SiC single crystal is grown at the crystal growth temperature.

Provided is a method for producing a SiC single crystal which can suppress generation of SiC polycrystals. The method according to the present embodiment is in accordance with a solution growth method. The method for producing a SiC single crystal according to the present embodiment comprises a power-output increasing step, a contact step, and a growth step. In the power-output increasing step, high-frequency power output of an induction heating device is increased to crystal-growth high-frequency power output. In the contact step, a SiC seed crystal is brought into contact with a SiC solution. The high-frequency power output of the induction heating device in the contact step is more than 80% of the crystal-growth high-frequency power output. The temperature of the SiC solution in the contact step is less than a crystal growth temperature. In the growth step, the SiC single crystal is grown at the crystal growth temperature.

The disclosure relates to a method for making semimetal compound of Pt. The semimetal compound is a single crystal material of PtTe.sub.2. The method comprises: placing pure Pt and pure Te in a reacting chamber as reacting materials; evacuating the reacting chamber to be vacuum less than 10 Pa; heating the reacting chamber to a first temperature from 600 degree Celsius to 800 degree Celsius and keeping for 24 hours to 100 hours; cooling the reacting chamber to a second temperature from 400 degree Celsius to 500 degree Celsius and keeping for 24 hours to 100 hours at a cooling rate from 1 degree Celsius per hour to 10 degree Celsius per hour to obtain a crystal material of PtTe.sub.2; and separating the excessive reacting materials from the crystal material of PtTe.sub.2.

The disclosure relates to a method for making semimetal compound of Pt. The semimetal compound is a single crystal material of PtTe.sub.2. The method comprises: placing pure Pt and pure Te in a reacting chamber as reacting materials; evacuating the reacting chamber to be vacuum less than 10 Pa; heating the reacting chamber to a first temperature from 600 degree Celsius to 800 degree Celsius and keeping for 24 hours to 100 hours; cooling the reacting chamber to a second temperature from 400 degree Celsius to 500 degree Celsius and keeping for 24 hours to 100 hours at a cooling rate from 1 degree Celsius per hour to 10 degree Celsius per hour to obtain a crystal material of PtTe.sub.2; and separating the excessive reacting materials from the crystal material of PtTe.sub.2.

A crystal growth apparatus includes a pressure-resistant vessel; a plurality of support tables arranged inside the pressure-resistant vessel; inner vessels each placed over the support tables, respectively; growth vessels contained the inner vessels, respectively; a heating means for heating the growth vessels; and a central rotating shaft connected to the support tables. The central rotating shaft is distant from central axes of the inner vessels, respectively. A seed crystal, a raw material of the Group 13 element and a flux are charged in each of the growth vessels, and the growth vessels are heated to form a melt and a nitrogen-containing gas is supplied to the melt to grow a crystal of a nitride of said Group 13 element while the central rotating shaft is rotated.