WO2013125161A1 - Dispositif destiné à la production de monocristal et procédé destiné à la production de monocristal - Google Patents

Dispositif destiné à la production de monocristal et procédé destiné à la production de monocristal Download PDF

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Publication number
WO2013125161A1
WO2013125161A1 PCT/JP2013/000527 JP2013000527W WO2013125161A1 WO 2013125161 A1 WO2013125161 A1 WO 2013125161A1 JP 2013000527 W JP2013000527 W JP 2013000527W WO 2013125161 A1 WO2013125161 A1 WO 2013125161A1
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WO
WIPO (PCT)
Prior art keywords
chamber
single crystal
carrier gas
heat insulating
crucible
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Application number
PCT/JP2013/000527
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English (en)
Japanese (ja)
Inventor
添田　聡
敏史 藤井
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信越半導体株式会社
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Application filed by 信越半導体株式会社 filed Critical 信越半導体株式会社
Publication of WO2013125161A1 publication Critical patent/WO2013125161A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B15/00—Single-crystal growth by pulling from a melt, e.g. Czochralski method
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/02—Elements
    • C30B29/06—Silicon

Definitions

  • the present invention relates to a single crystal manufacturing apparatus and a single crystal manufacturing method for manufacturing a single crystal using the Czochralski method (hereinafter referred to as “CZ method”).
  • a CZ method as a manufacturing method of a single crystal which is a basic material of a semiconductor integrated circuit.
  • a high-purity polycrystal is filled in a crucible provided in a chamber, heated and melted by a heater to form a raw material melt, seeded with a seed crystal in the raw material melt, and seeded. Thereafter, by pulling up the seed crystal while rotating it, the single crystal is grown below the seed crystal to produce a cylindrical single crystal.
  • a CZ single crystal manufacturing apparatus for growing a single crystal by the CZ method usually has a main chamber composed of at least three of a water-cooled bottom portion, a side portion, and an upper portion, and a crucible is arranged at the center thereof.
  • a heater surrounds the crucible. Further, the periphery of the heater is covered with a graphite member or a heat insulating material.
  • HZ hot zone
  • the gas flows between the crucible, the heater, and the heat insulating cylinder, and the carrier gas is also passed between the heat insulating cylinder covering the periphery and the inner wall of the chamber.
  • the oxide adhering to the upper part of the chamber falls into the raw material melt to inhibit single crystallization. Therefore, in recent years, a structure in which the linear velocity of the carrier gas is increased under reduced pressure and the oxide is quickly exhausted downward through the vicinity of the heater and the crucible has become the mainstream.
  • the entire HZ is placed directly on the bottom of the chamber. Due to the increasing importance of heat insulation efficiency due to the recent increase in the size of members, the side and bottom of the HZ structure are completely closed except for holes for exhaust and electrodes. ing.
  • the HZ structure is often provided with a heat shield covering the periphery of the single crystal, but has a certain gap above the HZ.
  • several improved structures in which the carrier gas passes between the heat insulating material covering the periphery of the crucible and the side surface in the chamber have been proposed. For example, the manufacturing method described in Patent Document 1 uses a heater and a crucible. It does not block the flow of the nearby carrier gas.
  • the carrier gas is once passed between the heat insulating cylinder and the side and bottom surfaces in the chamber as much as possible.
  • the carrier gas flow in the vicinity of the heater and the crucible is completely stopped. No.
  • a hole is finally made between the crucible and the heat insulating cylinder and taken inward, and the carrier gas is exhausted from the bottom of the HZ, the hole causes energy loss.
  • the aim of the invention is to prevent the heater or internal graphite material that has become high temperature from reacting with the oxide and deteriorating, and not to enhance the heat insulation effect.
  • the HZ structure is designed so as to reduce the energy loss by using a carbon fiber heat insulating material or the like, but this is limited and insufficient.
  • the present invention has been made in view of the above problems, and reduces the energy loss due to cooling water flowing through the chamber and saves power, thereby reducing the cost and the single crystal manufacturing apparatus and single crystal
  • An object is to provide a manufacturing method.
  • the present invention provides a chamber having a water cooling mechanism, a crucible disposed in the chamber, a heater disposed around the crucible, and a heat insulation disposed around the heater.
  • a single crystal manufacturing apparatus comprising a cylinder and pulling up a single crystal from a raw material melt contained in the crucible by a Czochralski method, and supplied from the upper part of the chamber between the heat insulating cylinder and a side surface in the chamber
  • a single crystal manufacturing apparatus is provided, wherein a gap through which the carrier gas passes is provided, and all of the carrier gas is exhausted from the bottom of the chamber via the gap.
  • a bottom gap communicating with the gap through which the carrier gas passes is provided between the heat insulating cylinder and the chamber bottom.
  • the device can be evacuated without going through the region.
  • the formation area of the bottom gap is 30% or more of the surface area of the bottom in the chamber.
  • the area where the oxide adheres to the bottom of the chamber can be increased, resulting in a device capable of obtaining a better heat insulating effect. Furthermore, the area in which the heat insulating cylinder is in contact with the bottom surface of the chamber is surely reduced, so that the energy generated by the heater can be further reduced from being taken away by the cooling water flowing through the bottom of the chamber.
  • the present invention also provides a method for producing a single crystal, characterized in that a single crystal is produced by the single crystal production apparatus.
  • the single crystal of the next batch is manufactured without removing the oxide attached to the side surface and bottom of the chamber.
  • the furnace pressure in the chamber during the production of the single crystal is preferably 50 to 300 hPa.
  • the linear velocity of the carrier gas can be increased, and the amount of oxide adhering to HZ can be reduced. Furthermore, the oxide adhering to the upper part of the chamber can be prevented from falling into the melt and adversely affecting the production of the single crystal.
  • the present invention when a single crystal is manufactured by the CZ method, the heat insulating effect of the oxide attached to the side surface and the bottom of the chamber and the installation area of the heat insulating cylinder on the bottom surface of the chamber are reduced. As a result, it is possible to reduce the power consumption while preventing the cooling water flowing in the chamber from depriving the energy generated by the heater, and it is possible to reduce the cost.
  • FIG. It is the figure which showed the carrier gas flow (a) of the HZ structure of this invention, and the oxide adhesion condition (b). It is the figure which showed transition of the power consumption of each 8 batch of an Example (this invention) when the power consumption of 1 batch of a comparative example (conventional method) is set to 100.
  • FIG. It is the figure which showed the carrier gas flow (a) of the conventional HZ structure, and the oxide adhesion condition (b).
  • the present inventors pay attention to the fact that the oxide attached to the inner wall of the chamber exerts a stable heat insulating effect at high temperature, and without passing the carrier gas through the region between the crucible and the heat insulating cylinder, all. It is found that the carrier gas can be exhausted through the heat insulating cylinder and the side and bottom surfaces in the chamber, thereby allowing the oxide to adhere widely to the inner wall of the chamber to obtain a heat insulating effect, thereby reducing the above energy loss. Was completed.
  • FIG. 1A shows the carrier gas flow in the apparatus of the present invention
  • FIG. 1B shows the state of oxide deposition in the apparatus of the present invention.
  • a crucible 3 containing a raw material melt 2 and a heater 4 are arranged around the crucible 3 containing a raw material melt 2, and a heat insulating cylinder 5 is arranged around the crucible 3.
  • a carrier gas 6 is supplied from the upper part of the chamber 1 and is exhausted to the outside through the exhaust gas pipe 7 at the bottom of the chamber 1 through the chamber 1.
  • the chamber 1 is made of a metal such as stainless steel, and is protected from being damaged by heat by circulating cooling water.
  • the crucible 3 is made of graphite on the outer side and made of quartz on the inner side for accommodating the raw material.
  • the heater 4 is a resistance heating made of graphite.
  • the heat insulating cylinder 5 is mainly made of carbon fiber in order to improve heat insulating properties and heat resistance.
  • the carrier gas 6 is an inert gas such as argon. However, these are not particularly limited.
  • the carrier gas 6 supplied from the upper part of the chamber 1 causes the gap 9 between the heat insulating cylinder 5 and the side surface in the chamber 1 and the heat insulating cylinder 5 and the chamber 1. It is exhausted to the outside of the chamber 1 through a bottom gap 10 between the bottom of the chamber 1 and the bottom of the chamber 1.
  • the oxide 8 adheres widely to the inner wall of the chamber 1 as shown in FIG.
  • the adhesion of the oxide 8 on the upper portion of the chamber 1 and the exhaust gas pipe 7 is very small as compared with the conventional case described later.
  • the exhaust gas pipe 7 must be cleaned between batches, but in the present invention, a plurality of batches can be continued without cleaning the exhaust gas pipe 7. Further, since the high-temperature carrier gas 6 that has passed through the vicinity of the heater 4 is not exhausted through the exhaust gas pipe 7 as it is conventionally, the energy loss through the exhaust gas pipe 7 is also reduced.
  • a bottom gap 10 communicating with the gap 9 through which the carrier gas 6 passes is provided between the heat insulating cylinder 5 and the chamber 1.
  • the formation region of the bottom gap 10 is 30% or more of the surface area of the bottom in the chamber 1.
  • the area where the oxide 8 adheres to the bottom in the chamber 1 can be increased, and a good heat insulating effect can be obtained.
  • the area where the heat insulating cylinder 5 is in contact with the bottom surface of the chamber 1 is reliably reduced, and it is possible to further reduce the loss of energy generated by the heater 4 by the cooling water flowing through the bottom of the chamber 1.
  • the formation region of the bottom gap 10 is preferably 90% or less of the surface area of the bottom in the chamber 1.
  • the carrier gas 6 supplied from the upper part of the chamber 1 passes through the region between the crucible 3 and the heat insulating cylinder 5 as shown in FIG. Exhausted to the outside of the chamber 1.
  • the oxide 8 generated during the production of the single crystal is more adhered to the upper portion of the chamber 1 and the exhaust gas pipe 7 than in the case of the present invention.
  • the effect of reducing the energy loss from the chamber 1 is small, and as described above, the exhaust gas pipe 7 must be cleaned between batches in the conventional method, and the cycle time is shorter than in the case of the present invention. Increases productivity.
  • a single crystal can be manufactured using the single crystal manufacturing apparatus of the present invention described above.
  • a method for producing a single crystal a high-purity polycrystal is filled in a crucible provided in a chamber, heated and melted by a heater to form a raw material melt, and a seed crystal is deposited in the raw material melt.
  • a CZ method is used in which a single crystal is grown under the seed crystal by seeding and then pulling up while rotating the seed crystal to produce a cylindrical single crystal.
  • the carrier gas 6 supplied from the upper part of the chamber 1 is exhausted from the exhaust gas pipe 7 to the outside of the chamber 1 through the gap 9 and the bottom gap 10. The Thereby, the oxide 8 adheres widely to the inner wall of the chamber 1, and a good heat insulating effect can be obtained.
  • FIG. 1 (b) it is preferable to carry out the production of a single crystal of the next batch without removing the oxide 8 adhering to the side and bottom of the chamber 1.
  • the single crystal manufacturing method which can reduce cycle time can be provided.
  • the oxide 8 adhering to the upper portion of the chamber 1 is removed in order to prevent the oxide 8 from falling during crystal growth and exerting an adverse effect.
  • the furnace pressure in the chamber 1 during the production of the single crystal is kept at 50 to 300 hPa, which is lower than the normal pressure.
  • the linear velocity of the carrier gas 6 can be increased, and the amount of the oxide 8 attached to HZ can be reduced.
  • it can be set as the single-crystal manufacturing method which can prevent the oxide 8 adhering to the upper part of the chamber 1 falling in the raw material melt 2, and having a bad influence on single-crystal manufacture.
  • Example and comparative examples In both the examples and comparative examples, 180 kg of silicon polycrystalline raw material was charged into a crucible having a diameter of 65 cm (26 inches) to produce a silicon single crystal having a diameter of 200 mm. The amount of gas and the pressure in the furnace were 100 l / min and 100 hPa (100 mbar), respectively.
  • the gap between the side surface in the chamber and the heat insulating cylinder was about 20 mm. Further, by placing a graphite material raising part on the HZ bottom, the bottom gap was formed by raising the HZ bottom by 50 mm, and the exhaust gas pipe on the bottom of the chamber was exposed. Furthermore, the formation area of the chamber bottom gap was about 50% of the surface area of the chamber bottom.
  • the comparative example manufactured the single crystal by the conventional method using the apparatus as shown in FIG. In this device, almost all of the carrier gas is exhausted as it is through the vicinity of the heater.
  • the power consumption of the example was 96 when the power consumption of the comparative example (conventional method) was set to 100. At this time, the adhesion of oxide in the exhaust gas pipe was slight.
  • the same operation was repeated continuously for 8 batches.
  • the oxide at the top of the chamber falls into the raw material melt in the crucible during operation and adversely affects the production of single crystals, it was removed after each batch, but the oxide attached to the side and bottom in the chamber Without removal, the next batch of single crystals was produced.
  • the power consumption of the comparative example (conventional method) was set to 100
  • the power consumption in the example of the eighth batch (the present invention) was 90.
  • the oxide deposited on the inner wall of the chamber after 8 batches was about 2 to 3 mm at the upper side of the chamber and about 1 mm at the lower and bottom of the side.
  • the present invention is not limited to the above embodiment.
  • the above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

La présente invention concerne un dispositif de production de monocristal, qui comprend une chambre équipée d'un mécanisme de refroidissement par eau, un creuset disposé à l'intérieur de la chambre, des dispositifs de chauffage disposés autour du creuset et des tuyaux d'isolation disposés autour des dispositifs de chauffage, et qui tire un monocristal depuis une masse fondue de matériau brut contenue dans le creuset par le procédé de Czochralski. Le dispositif selon l'invention est caractérisé en ce que des espaces sont situés entre les tuyaux d'isolation et les côtés internes de la chambre, à travers lesquels un gaz support alimenté depuis la partie supérieure de la chambre passe, et la totalité du gaz support est évacuée à partir de la partie de fond de la chambre via les espaces. Par conséquent, un dispositif destiné à la production d'un monocristal et un procédé destiné à la production d'un monocristal présentant des effets d'isolation maximaux peuvent être décrits.
PCT/JP2013/000527 2012-02-24 2013-01-31 Dispositif destiné à la production de monocristal et procédé destiné à la production de monocristal WO2013125161A1 (fr)

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JP2012-039048 2012-02-24
JP2012039048A JP5776587B2 (ja) 2012-02-24 2012-02-24 単結晶製造方法

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WO2013125161A1 true WO2013125161A1 (fr) 2013-08-29

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105525342A (zh) * 2015-12-22 2016-04-27 英利集团有限公司 一种直拉法制备大尺寸单晶硅棒的方法及单晶炉

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6197680B2 (ja) * 2014-02-12 2017-09-20 信越半導体株式会社 シリコン単結晶製造装置

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Publication number Priority date Publication date Assignee Title
JPS55113695A (en) * 1979-02-23 1980-09-02 Nippon Telegr & Teleph Corp <Ntt> Single crystal growing device
JPH05117074A (ja) * 1991-10-29 1993-05-14 Komatsu Electron Metals Co Ltd 半導体単結晶製造方法および製造装置
JPH0687687A (ja) * 1992-03-31 1994-03-29 Shin Etsu Handotai Co Ltd シリコン単結晶引上げ装置
JPH06122586A (ja) * 1992-10-09 1994-05-06 Kawasaki Steel Corp 単結晶引上げ装置
JPH06247788A (ja) * 1993-02-22 1994-09-06 Nippon Steel Corp シリコン単結晶の製造方法およびその装置
JPH06271396A (ja) * 1993-03-22 1994-09-27 Nippon Steel Corp シリコン単結晶の製造装置
JPH06279166A (ja) * 1993-03-30 1994-10-04 Nippon Steel Corp シリコン単結晶の製造方法およびその装置
JPH06298589A (ja) * 1993-04-09 1994-10-25 Nippon Steel Corp シリコン単結晶の製造方法およびこれに用いられる冷却筒
JP2002321997A (ja) * 2001-04-20 2002-11-08 Shin Etsu Handotai Co Ltd シリコン単結晶の製造装置及びそれを用いたシリコン単結晶の製造方法
JP2004137089A (ja) * 2002-10-15 2004-05-13 Toshiba Ceramics Co Ltd シリコン単結晶引上装置
JP2010501466A (ja) * 2006-09-01 2010-01-21 オクメティック オサケユフティオ ユルキネン 結晶製造

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JP4103593B2 (ja) * 2001-02-28 2008-06-18 信越半導体株式会社 固形状多結晶原料のリチャージ管及びそれを用いた単結晶の製造方法
JP4862836B2 (ja) * 2008-02-05 2012-01-25 信越半導体株式会社 単結晶製造装置及び単結晶製造方法
JP2011093778A (ja) * 2009-09-29 2011-05-12 Shin Etsu Handotai Co Ltd シリコン単結晶ウェーハおよびシリコン単結晶の製造方法

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS55113695A (en) * 1979-02-23 1980-09-02 Nippon Telegr & Teleph Corp <Ntt> Single crystal growing device
JPH05117074A (ja) * 1991-10-29 1993-05-14 Komatsu Electron Metals Co Ltd 半導体単結晶製造方法および製造装置
JPH0687687A (ja) * 1992-03-31 1994-03-29 Shin Etsu Handotai Co Ltd シリコン単結晶引上げ装置
JPH06122586A (ja) * 1992-10-09 1994-05-06 Kawasaki Steel Corp 単結晶引上げ装置
JPH06247788A (ja) * 1993-02-22 1994-09-06 Nippon Steel Corp シリコン単結晶の製造方法およびその装置
JPH06271396A (ja) * 1993-03-22 1994-09-27 Nippon Steel Corp シリコン単結晶の製造装置
JPH06279166A (ja) * 1993-03-30 1994-10-04 Nippon Steel Corp シリコン単結晶の製造方法およびその装置
JPH06298589A (ja) * 1993-04-09 1994-10-25 Nippon Steel Corp シリコン単結晶の製造方法およびこれに用いられる冷却筒
JP2002321997A (ja) * 2001-04-20 2002-11-08 Shin Etsu Handotai Co Ltd シリコン単結晶の製造装置及びそれを用いたシリコン単結晶の製造方法
JP2004137089A (ja) * 2002-10-15 2004-05-13 Toshiba Ceramics Co Ltd シリコン単結晶引上装置
JP2010501466A (ja) * 2006-09-01 2010-01-21 オクメティック オサケユフティオ ユルキネン 結晶製造

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105525342A (zh) * 2015-12-22 2016-04-27 英利集团有限公司 一种直拉法制备大尺寸单晶硅棒的方法及单晶炉

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