Sumco Corporation

Koichi Maegawa

Yasufumi Kawakami

Fukuo Ogawa

Yasuhito Narushima

Takuya Yotsui

Mitsuo Yoshihara

Ayumi Kihara

Shinya Fukushima

Yuuji Tsutsumi

Satoru Hamakawa

Tomohiro Onizuka

A method for producing an n-type monocrystalline silicon that includes pulling up a monocrystalline silicon from a silicon melt containing a main dopant in a form of red phosphorus to grow the monocrystalline silicon. The monocrystalline silicon exhibits an electrical resistivity ranging from 1.7 mΩcm to 2.0 mΩcm, and is pulled up using a quartz crucible whose inner diameter ranges from 1.7-fold to 2.0-fold relative to a straight-body diameter of the monocrystalline silicon.

N-type silicon single crystal production method, n-type silicon single crystal ingot, silicon wafer, and epitaxial silicon wafer

A production method of monocrystalline silicon includes: growing the monocrystalline silicon having a straight-body diameter in a range from 301 mm to 330 mm that is pulled up through a Czochralski process from a silicon melt including a dopant in a form of arsenic; controlling a resistivity of the monocrystalline silicon at the straight-body start point to fall within a range from 2.50 mΩcm to 2.90 mΩcm; and subsequently sequentially decreasing the resistivity of the monocrystalline silicon to fall within a range from 1.6 mΩcm to 2.0 mΩcm at a part of the monocrystalline silicon.

Method for producing silicon single crystal

A production method of monocrystalline silicon includes: growing the monocrystalline silicon having a straight-body diameter in a range from 301 mm to 330 mm that is pulled up through a Czochralski process from a silicon melt including a dopant in a form of red phosphorus; controlling a resistivity of the monocrystalline silicon at a straight-body start point to fall within a range from 1.20 m&#x3a9;cm to 1.35 m&#x3a9;cm; and subsequently sequentially decreasing the resistivity of the monocrystalline silicon to fall within a range from 0.7 m&#x3a9;cm to 1.0 m&#x3a9;cm at a part of the monocrystalline silicon.

In a producing method of an n-type monocrystalline silicon by pulling up a monocrystalline silicon from a silicon melt containing a main dopant in a form of red phosphorus to grow the monocrystalline silicon, the monocrystalline silicon exhibiting an electrical resistivity ranging from 0.5 m&#x3a9;cm to 1.0 m&#x3a9;cm is pulled up using a quartz crucible whose inner diameter ranges from 1.7-fold to 2.3-fold relative to a straight-body diameter of the monocrystalline silicon.

A deposit removing device disclosed herein removes a deposit that adheres to an exhaust pipe through which gas is exhausted from a chamber that manufactures a semiconductor crystal. The deposit removing device includes: a valve that opens and closes an exhaust outlet that communicates with the exhaust pipe; a sealing cover and a fixed table configured to store the valve, into which an inert gas is introduceable, and configured to isolate the exhaust outlet from the outside; and an exhaust outlet opening/closing portion that includes a cylinder for driving the valve and a cylinder for driving the sealing cover or the fixed table. The cylinder drives the valve to open and close the exhaust outlet, and the cylinder drives the sealing cover or the fixed table to introduce the atmosphere into the sealing cover.

Deposit removing device and deposit removing method

A cleaning method includes a first removal step of causing an inert gas to which a pulsation is applied to flow into an exhaust pipe after a silicon single crystal doped with an n-type dopant is produced, to peel and remove a deposit; and a second removal step of causing an atmospheric air to which no pulsation is applied to flow into the exhaust pipe through a chamber to burn a part of the deposit with the atmospheric air, the part being not removable in the first removal step, and peel and remove a burned substance of the deposit.

Cleaning method, method for producing silicon single crystal, and cleaning device

An n-type silicon single crystal production method of pulling up a silicon single crystal from a silicon melt containing red phosphorus as a principal dopant and growing the silicon single crystal by the Czochralski process, the method including: controlling electrical resistivity at a start position of a straight body portion of the silicon single crystal to 0.80 m&#x3a9;cm or more and 1.05 m&#x3a9;cm or less; and sequentially lowering the electrical resistivity of the silicon single crystal as the silicon single crystal is up and grown, thereby adjusting electrical resistivity of a part of the silicon single crystal to 0.5 m&#x3a9;m or more and less than 0.6 m&#x3a9;cm.

A silicon single crystal production method includes pulling up and growing a silicon single crystal from silicon melt containing red phosphorus as a dopant by Czochralski process. The silicon single crystal is intended for a 200-mm-diameter wafer. The silicon single crystal includes a straight body with a diameter in a range from 201 mm to 230 mm. The straight body includes a straight-body start portion with an electrical resistivity in a range from 0.8 m&#x3a9;cm to 1.2 m&#x3a9;cm. A crystal rotation speed of the silicon single crystal is controlled to fall within a range from 17 rpm to 40 rpm for at least part of a shoulder-formation step for the silicon single crystal.

A manufacturing method of monocrystalline silicon includes: disposing a flow regulator including a body in a form of an annular plate, provided under a heat shield, surrounding monocrystalline silicon; controlling an internal pressure of a chamber to 20 kPa or more during growth of monocrystalline silicon; keeping the flow regulator spaced from a dopant-added melt; and introducing inert gas into between the monocrystalline silicon and the heat shield to divide the inert gas into a first flow gas and a second flow gas.

Method for manufacturing silicon single crystal, flow straightening member, and single crystal pulling device

Disclosed is an electromagnetic casting method of polycrystalline silicon which is characterized in that polycrystalline silicon is continuously cast by charging silicon raw materials into a bottomless cold mold, melting the silicon raw materials using electromagnetic induction heating, and pulling down the molten silicon to solidify it, wherein the depth of solid-liquid interface before the start of the final solidification process is decreased by reducing a pull down rate of ingot in a final phase of steady-state casting. By adopting the method, the region of precipitation of foreign substances in the finally solidified portion of ingot can be reduced and cracking generation can be prevented upon production of a polycrystalline silicon as a substrate material for a solar cell.

Electromagnetic casting method and apparatus for polycrystalline silicon

Provided is a continuous casting method of a silicon ingot for continuously casting the silicon ingot by arranging, inside an induction coil, a bottomless cold crucible having a part along an axial direction that is circumferentially divided into a plurality of strip elements, forming molten silicon inside the cold crucible through electromagnetic induction heating by the induction coil, and solidifying the molten silicon while pulling it down from the cold crucible, wherein as the cold crucible, used is a cold crucible with Ni&#x2014;B alloy plating on a portion in the inner surface thereof that faces the outer side surface of the molten silicon and the outer surface of the silicon ingot. The method can reduce the damage to the inner surface of the cold crucible, in addition to the contamination of cast ingots with impurities.

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Tokyo, Japan

Koichi Maegawa