Sumco Techxiv Corporation

Sumco Corporation

Fukuo Ogawa

Yasuhito Narushima

Toshimichi Kubota

Shinichi Kawazoe

Koichi Maegawa

Yasufumi Kawakami

Tomohiro Fukuda

Masayuki Uto

Tsuneaki Tomonaga

Ayumi Kihara

Takuya Yotsui

Yuuji Tsutsumi

Tuneaki Tomonaga

Yasuyuki Ohta

Masahiro Irokawa

Shinsuke Nishihara

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

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

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.

Method for producing 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

The sublimation speed of dopant can be precisely controlled without being influenced by a change over time of intra-furnace thermal environment. A dopant supply unit equipped with an accommodation chamber and a supply tube is provided. A sublimable dopant is accommodated. Upon sublimation of the dopant within the accommodation chamber, the sublimed dopant is introduced into a melt. The dopant within the accommodation chamber of the dopant supply unit is heated. The amount of heating by means of heating means is controlled so as to sublime the dopant at a desired sublimation speed. The dopant is supplied to the melt so that the dopant concentration until the first half of a straight body portion of the silicon single crystal is in the state of low concentration or non-addition. After the first half of the straight body portion of the silicon single crystal is formed, the dopant is supplied to the melt so that every portion of the crystal is in the state where the dopant is added to a desired high concentration.

Producing method and apparatus of silicon single crystal, and silicon single crystal ingot

A smonocrystalline silicon include a straight body formed without generating a remelt growth area of 200 &#x3bc;m or more in a height in a growth direction. Growth striations, which are formed radially across the straight body, include a growth striation with an outer end interrupted by another growth striation not to reach a peripheral portion of the straight body. The remelt growth area has the growth striation with the interrupted outer end.

Manufacturing method of monocrystalline silicon and monocrystalline silicon

A manufacturing method of a single crystal uses a single-crystal pull-up apparatus includes: adding the red phosphorus to the silicon melt so that a resistivity of the single crystal falls in a range from 0.7 m&#x3a9;&#xb7;cm to 0.9 m&#x3a9;&#xb7;cm; subjecting an evaluation silicon wafer obtained from the single crystal to a heat treatment in which the evaluation silicon wafer is heated at 1200 degrees C. for 30 seconds in a hydrogen atmosphere; and pull-up the single crystal while appropriately controlling a period for a temperature of the single crystal to be in a range of 570&#xb1;70 degrees C. so that the number of pits generated on the evaluation silicon wafer becomes 0.1/cmor less.

Method for producing single crystal, and method for producing silicon wafer

A graphite member utilized in a pulling device for pulling a silicon single crystal is provided. An edge part of the graphite member is rounded off which is exposed to a reactive gas. The graphite member may comprise: a plate part having a thickness of 't' wherein a curvature radius of 'r' satisfies the formula: t/8&#x2266;r&#x2266;t/4.

Silicon single crystal pulling device and graphite member used therein

A process for production of a silicon ingot, by which a silicon ingot exhibiting a low resistivity even in the top portion can be produced. The process for the production of a silicon ingot includes withdrawing a silicon seed crystal from a silicon melt to grow a silicon single crystal, with the silicon seed crystal and the silicon melt containing dopants of the same kind. The process includes the dipping step of dipping a silicon seed crystal containing a dopant in a specific concentration in a silicon melt in such a manner that the temperature difference between both falls within the range of 50 to 97K, and the growing step of growing a silicon single crystal withdrawn after the dipping to form a silicon ingot, the growing step being conducted by using a single crystal puller provided with a thermal shield plate for shielding against radiant heat emitted from the silicon melt and controlling the distance between the thermal shield plate and the silicon melt within a specific range.

Processes for production of silicon ingot, silicon wafer and epitaxial wafer, and silicon ingot

For manufacturing a monocrystal, a monocrystal pulling-up device controls pressure within a flow straightening cylinder to be from 33331 Pa to 79993 Pa and a flow velocity of inert gas in the cylinder to be from 0.06 m/sec to 0.31 m/sec (0.005 to 0.056 SL/min&#xb7;cm) during a post-addition-pre-growth period. By controlling the flow velocity of the inert gas to be in the above-described range during the post-addition-pre-growth period, the inert gas flows smoothly even when the pressure within the cylinder is relatively high. Evaporation of a volatile dopant because of a reverse flow of the inert gas can be restrained. The volatile dopant can be prevented from adhering to the flow straightening cylinder in an amorphous state, and the volatile dopant can be prevented from dropping into a melt or sticking on the melt while growing a crystal. Foulings can be easily removed.

Method of manufacturing monocrystal, flow straightening cylinder, and monocrystal pulling-up device

A silicon single crystal pull-up apparatus includes a pull-up furnace, a sample chamber in which a sublimable dopant is housed, a sample tube which can be raised and lowered between the interior of the sample chamber and the interior of the pull-up furnace, a raising and lowering means for raising and lowering the sample tube, a supply pipe which is installed inside the pull-up furnace and supplies the sublimable dopant to a melt, and a connection means for connecting the sample tube and the supply pipe. The connection means is constructed from a ball joint structure comprising a convex member which projects from one end of the sample tube and a concave member which is provided at one end of the supply pipe and is formed to be engageable with the convex member. The contact surfaces of the convex member and the concave member are formed to be curved surfaces.

Silicon single crystal pull-up apparatus that pulls a doped silicon single crystal from a melt

The present invention provides a technique which enables production of single crystal silicon having relatively low resistivity by preventing cell growth during crystal growth from occurring, especially in a case where a relatively large amount of dopant is added to a molten silicon raw material. Specifically, the present invention provides a method of producing single crystal silicon by the Czochralski process, comprising producing single crystal silicon having relatively low resistivity by controlling a height of a solid-liquid interface when the single crystal silicon is pulled up.

Method of producing single crystal silicon

In consideration of influence of segregation, an evaporation area of a volatile dopant and influence of pulling-up speed at the time of manufacturing a monocrystal using a monocrystal pulling-up device, an evaporation speed formula for calculating evaporation speed of the dopant is derived. At predetermined timing during pulling-up, gas flow volume and inner pressure in a chamber are controlled such that a cumulative evaporation amount of the dopant, calculated based on the evaporation speed formula, becomes a predetermined amount. A difference between a resistivity profile of the monocrystal predicted based on the evaporation speed formula and an actual resistivity profile is made small. Since no volatile dopant is subsequently added, increase in workload on an operator, increase of manufacturing time, an increase in amorphous adhering to the inside of the chamber, and an increase in workload at the time of cleaning the inside of the chamber can be prevented.

Growing community of inventors

Omura, Japan

Fukuo Ogawa