Abstract: A method for manufacturing a solar cell, a method for manufacturing a monocrystalline silicon wafer and a photovoltaic module. The method for manufacturing a monocrystalline silicon wafer includes: providing a monocrystalline silicon rod; squaring the monocrystalline silicon rod to form a quasi-square silicon rod with quasi-square cross-section having an arc, a length of the arc being not less than 15 mm; slicing the quasi-square silicon rod to form at least one quasi-square silicon wafer having the arc. The method for manufacturing at least one solar cell includes: using the method described above to obtain a quasi-square silicon wafer having an arc; forming a first solar cell by processing the quasi-square silicon wafer; scribing the first solar cell to obtain a square-shaped sub-solar cell and at least one strip-shaped sub-solar cell. The above methods improve the utilization rate of the monocrystalline silicon rod and reduce production cost.

Abstract: A method for preparing a silicon single crystal rod is provided. The method includes a crystal pulling process including a melt contacting operation, a seeding operation, a shoulder releasing operation, a shoulder rotating operation, a diameter equalizing operation, and a closing operation in sequence. Each operation of the crystal pulling process has a furnace pressure less than or equal to 500 Pa and a pumping rate greater than or equal to 1000 m3/h.

Abstract: A method for manufacturing a solar cell, a method for manufacturing a monocrystalline silicon wafer and a photovoltaic module. The method for manufacturing a monocrystalline silicon wafer includes: providing a monocrystalline silicon rod; squaring the monocrystalline silicon rod to form a quasi-square silicon rod with quasi-square cross-section having an arc, a length of the arc being not less than 15 mm; slicing the quasi-square silicon rod to form at least one quasi-square silicon wafer having the arc. The method for manufacturing at least one solar cell includes: using the method described above to obtain a quasi-square silicon wafer having an arc; forming a first solar cell by processing the quasi-square silicon wafer; scribing the first solar cell to obtain a square-shaped sub-solar cell and at least one strip-shaped sub-solar cell. The above methods improve the utilization rate of the monocrystalline silicon rod and reduce production cost.

Abstract: Provided is an apparatus and a method for continuous crystal pulling. The apparatus includes: a crucible including a first sub-crucible and a second sub-crucible located at inner side of the first sub-crucible; a draft tube located above the crucible; and a delivery duct supplying materials to the crucible. A ratio of inner diameter of the second sub-crucible to outer diameter of the draft tube is ?1.05. In a first state, a distance between bottom surface of the draft tube and bottom surface of the crucible is a first distance, in a second state, a distance between bottom surface of the draft tube and bottom surface of the crucible is a second distance. The first distance is greater than the second distance. In the first and second states, a distance between a crystal-liquid interface in the crucible and the bottom surface of the draft tube remains substantially unchanged.

Abstract: Provided is a method for manufacturing at least one solar cell, a method for manufacturing a monocrystalline silicon wafer and a photovoltaic module. The method for manufacturing a monocrystalline silicon wafer includes: providing a monocrystalline silicon rod; squaring the monocrystalline silicon rod to form a quasi-square silicon rod with quasi-square cross-section having an arc, a length of the arc being not less than 15 mm; slicing the quasi-square silicon rod to form at least one quasi-square silicon wafer having the arc. The method for manufacturing at least one solar cell includes: using the method described above to obtain a quasi-square silicon wafer having an arc; forming a first solar cell by processing the quasi-square silicon wafer; scribing the first solar cell to obtain a square-shaped sub-solar cell and at least one strip-shaped sub-solar cell. The above methods improve the utilization rate of the monocrystalline silicon rod and reduce production cost.

Abstract: Provided is a method for preparing a gallium- and nitrogen-doped monocrystalline silicon using a Czochralski process, including: introducing a doping gas at least including a first amount of nitrogen into a molten mixture in a single crystal furnance; withdrawing a seed from the molten mixture while introducing the doping gas including a second amount of nitrogen into the molten mixture, a second ratio of the second amount of nitrogen to the doping gas being smaller than the first ratio; and upon occurrence of a shoulder of the monocrystalline silicon rod, adjusting the second amount of nitrogen to a third amount in such a manner that a third ratio of the third amount of nitrogen to the doping gas is greater than the second ratio, to form a monocrystalline silicon rod. A solar cell and a photovoltaic module including a gallium- and nitrogen-doped silicon wafer prepared therefrom are also provided.

Abstract: 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.

Abstract: Provided is an apparatus and a method for continuous crystal pulling. The apparatus includes: a crucible including a first sub-crucible and a second sub-crucible located at inner side of the first sub-crucible; a draft tube located above the crucible; and a delivery duct supplying materials to the crucible. A ratio of inner diameter of the second sub-crucible to outer diameter of the draft tube is ?1.05. In a first state, a distance between bottom surface of the draft tube and bottom surface of the crucible is a first distance, in a second state, a distance between bottom surface of the draft tube and bottom surface of the crucible is a second distance. The first distance is greater than the second distance. In the first and second states, a distance between a crystal-liquid interface in the crucible and the bottom surface of the draft tube remains substantially unchanged.

Abstract: 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.

Abstract: Provided is a method for preparing a gallium- and nitrogen-doped monocrystalline silicon using a Czochralski process, including: introducing a doping gas at least including a first amount of nitrogen into a molten mixture in a single crystal furnace; withdrawing a seed from the molten mixture while introducing the doping gas including a second amount of nitrogen into the molten mixture, a second ratio of the second amount of nitrogen to the doping gas being smaller than the first ratio; and upon occurrence of a shoulder of the monocrystalline silicon rod, adjusting the second amount of nitrogen to a third amount in such a manner that a third ratio of the third amount of nitrogen to the doping gas is greater than the second ratio, to form a monocrystalline silicon rod. A solar cell and a photovoltaic module including a gallium- and nitrogen-doped silicon wafer prepared therefrom are also provided.

Abstract: Provided is a method for manufacturing at least one solar cell, a method for manufacturing a monocrystalline silicon wafer and a photovoltaic module. The method for manufacturing a monocrystalline silicon wafer includes: providing a monocrystalline silicon rod; squaring the monocrystalline silicon rod to form a quasi-square silicon rod with quasi-square cross-section having an arc, a length of the arc being not less than 15 mm; slicing the quasi-square silicon rod to form at least one quasi-square silicon wafer having the arc. The method for manufacturing at least one solar cell includes: using the method described above to obtain a quasi-square silicon wafer having an arc; forming a first solar cell by processing the quasi-square silicon wafer; scribing the first solar cell to obtain a square-shaped sub-solar cell and at least one strip-shaped sub-solar cell. The above methods improve the utilization rate of the monocrystalline silicon rod and reduce production cost.

Abstract: The invention discloses (110) dislocation-free monocrystalline silicon and its preparation and the graphite heating system used. The process for preparation is as follows: clearing furnace and tidy the heat field; loading furnace; vacuumizing and argon charging; heating raw material; crystal seeding; expanding shoulder; rotating shoulder: speeding up the speed of shoulder-expanding; equal diameter: after shoulder-rotating, stabilize the crystal growth speed; finishing: turning off the power of crucible, decreasing the drawing rate manually; turning off the furnace. The graphite heating system includes: upper insulation column, lower insulation column and hearth tray arranged from the top down to form the external shell, and the peripheral surface is a stepped structure, and the thickness of the insulation layer of the upper insulation column is 20-30 mm, the thickness of the insulation layer of the lower insulation column is 60-70 mm, and the thickness of the insulation layer of the hearth tray is 70-80 mm.