The invention relates to a method for growing a bulk single crystal, wherein the method comprises the steps of inserting a starting material into a crucible, melting the starting material in the crucible by heating the starting material, arranging a thermal insulation lid at a distance above a melt surface of said melt such that at least a central part of the melt surface is covered by the lid, and growing the bulk single crystal from the melt by controllably cooling the melt with the thermal insulation lid arranged above the melt surface.

The invention relates to a method for growing a bulk single crystal, wherein the method comprises the steps of inserting a starting material into a crucible, melting the starting material in the crucible by heating the starting material, arranging a thermal insulation lid at a distance above a melt surface of said melt such that at least a central part of the melt surface is covered by the lid, and growing the bulk single crystal from the melt by controllably cooling the melt with the thermal insulation lid arranged above the melt surface.

A mono-crystalline silicon growth apparatus is provided. The mono-crystalline silicon growth apparatus includes a furnace, a support base disposed in the furnace, a crucible disposed on the support base, and a heating module. The support base and the crucible do not rotate relative to the heating module, and an axial direction is defined to be along a central axis of the crucible. The heating module is disposed at an outer periphery of the support base and includes a first heating unit, a second heating unit, and a third heating unit. The first heating unit, the second heating unit, and the third heating unit are respectively disposed at positions with different heights corresponding to the axial direction.

A mono-crystalline silicon growth apparatus is provided. The mono-crystalline silicon growth apparatus includes a furnace, a support base disposed in the furnace, a crucible disposed on the support base, and a heating module. The support base and the crucible do not rotate relative to the heating module, and an axial direction is defined to be along a central axis of the crucible. The heating module is disposed at an outer periphery of the support base and includes a first heating unit, a second heating unit, and a third heating unit. The first heating unit, the second heating unit, and the third heating unit are respectively disposed at positions with different heights corresponding to the axial direction.

A method for manufacturing a monocrystalline silicon with Czochralski process, including: providing polycrystalline silicon and dopant to quartz crucible in single crystal furnace and vacuumizing, melting the polycrystalline silicon under protective gas to obtain silicon melt; after temperature of the silicon melt is stable, immersing seed crystal into the silicon melt to start seeding, lifting a shield away from surface of the silicon melt to adjust distance between the shield and the silicon melt to first preset distance; after seeding, performing shouldering to pull the crystal to increase diameter of the crystal to preset width; starting constant-diameter body growth, lowering the shield towards the surface of the silicon melt to adjust the distance to second preset distance; after growth, entering a tailing stage during which the diameter of the crystal is reduced until the crystal is separated from the silicon melt; and cooling the crystal to obtain monocrystalline silicon.

A method for manufacturing a monocrystalline silicon with Czochralski process, including: providing polycrystalline silicon and dopant to quartz crucible in single crystal furnace and vacuumizing, melting the polycrystalline silicon under protective gas to obtain silicon melt; after temperature of the silicon melt is stable, immersing seed crystal into the silicon melt to start seeding, lifting a shield away from surface of the silicon melt to adjust distance between the shield and the silicon melt to first preset distance; after seeding, performing shouldering to pull the crystal to increase diameter of the crystal to preset width; starting constant-diameter body growth, lowering the shield towards the surface of the silicon melt to adjust the distance to second preset distance; after growth, entering a tailing stage during which the diameter of the crystal is reduced until the crystal is separated from the silicon melt; and cooling the crystal to obtain monocrystalline silicon.

An apparatus for manufacturing a single crystal by growing a single crystal according to a Czochralski method, the apparatus including: main chamber configured to house crucible configured to accommodate raw-material melt, and heater configured to heat raw-material melt; pulling chamber continuously provided at upper portion of main chamber and configured to accommodate single crystal grown and pulled; cooling cylinder extending from at least ceiling portion of main chamber toward raw-material melt so as to surround single crystal being pulled, cooling cylinder configured to be forcibly cooled with coolant; and auxiliary cooling cylinder fitted in an inside of cooling cylinder. Auxiliary cooling cylinder is made of any one or more materials of graphite, carbon composite, stainless steel, molybdenum, and tungsten. The auxiliary cooling cylinder has structure covering bottom surface of cooling cylinder facing raw-material melt. Gap between auxiliary cooling cylinder and bottom surface of cooling cylinder is 1.0 mm or less.

A cylinder assembly of a single crystal pulling apparatus and a single crystal pulling apparatus are provided in the present disclosure. The cylinder assembly includes an inner cylinder, an outer cylinder, an annular plate and a sleeve. The inner cylinder has a shape of inverted conical. An upper end of the inner cylinder is connected to an upper end of the outer cylinder. A lower end of the outer cylinder is hermetically connected to an outer edge of the annular plate. A lower end of the inner cylinder is fixedly connected to an upper surface of the annular plate. The sleeve passes through and is fixed in an annular opening of the annular plate.

A cylinder assembly of a single crystal pulling apparatus and a single crystal pulling apparatus are provided in the present disclosure. The cylinder assembly includes an inner cylinder, an outer cylinder, an annular plate and a sleeve. The inner cylinder has a shape of inverted conical. An upper end of the inner cylinder is connected to an upper end of the outer cylinder. A lower end of the outer cylinder is hermetically connected to an outer edge of the annular plate. A lower end of the inner cylinder is fixedly connected to an upper surface of the annular plate. The sleeve passes through and is fixed in an annular opening of the annular plate.

A bismuth-substituted rare earth iron garnet single crystal suitable for Faraday rotators and optical isolators with reduced insertion loss due to suppressed valence fluctuation of Fe ions is provided. The bismuth-substituted rare earth iron garnet single crystal of the present invention is characterized by the composition formula (Tb.sub.aLn.sub.bBi.sub.cMg.sub.3−(a+b+c))(Fe.sub.dGa.sub.eTi.sub.fPt.sub.5−(d+e+f))O.sub.12. In the composition formula above, 0.02≤f≤0.05, 0.02≤{3−(a+b+c)}≤0.08, and −0.01≤{3−(a+b+c)}−{f+5−(d+e+f)}≤0.01. Ln is a rare earth element and may be selected from Eu, Gd, Ho, Tm, Yb, Lu, and Y.