Magnetic Patents (Class 117/917)
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Patent number: 11891721Abstract: A crystal growing system can include a spool-balanced seed lift assembly for rotating and lifting a seed crystal supported by a cable. The seed crystal is supported along and rotated about a lift axis. The spool-balanced seed lift assembly includes a spool that rotates on, and has a center of gravity along, an axis that intersects the lift axis. As the spool rotates, it moves axially along its axis to avoid displacing the cable from the lift axis. A guide pulley positioned below the spool is used to direct the cable between the lift axis and a spool-tangent axis to minimize displacement of the cable as it is raised and rotated.Type: GrantFiled: June 3, 2021Date of Patent: February 6, 2024Assignee: Linton Kayex Technology Co., LtdInventors: Jiaqi Yin, John A. Reese, Joel C. Stefl
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Patent number: 11885038Abstract: A convection pattern estimation method of a silicon melt includes: applying a horizontal magnetic field of 0.2 tesla or more to a silicon melt in a rotating quartz crucible with use of a pair of magnetic bodies disposed across the quartz crucible; before a seed crystal is dipped into the silicon melt to which the horizontal magnetic field is applied; measuring temperatures at a first and second measurement points positioned on a first imaginary line that passes through a center of a surface of the silicon melt and is not in parallel with a central magnetic field line of the horizontal magnetic field as viewed vertically from above; and estimating a direction of a convection flow in a plane in the silicon melt orthogonal to the direction in which the horizontal magnetic field is applied on a basis of the measured temperatures of the first and second measurement points.Type: GrantFiled: February 27, 2019Date of Patent: January 30, 2024Assignee: SUMCO CORPORATIONInventors: Wataru Sugimura, Ryusuke Yokoyama, Toshiyuki Fujiwara, Toshiaki Ono
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Patent number: 11814745Abstract: 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?cm to 1.35 m?cm; and subsequently sequentially decreasing the resistivity of the monocrystalline silicon to fall within a range from 0.7 m?cm to 1.0 m?cm at a part of the monocrystalline silicon.Type: GrantFiled: June 15, 2018Date of Patent: November 14, 2023Assignee: SUMCO CORPORATIONInventors: Yasufumi Kawakami, Koichi Maegawa
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Patent number: 11814746Abstract: A lift assembly includes a lift housing, a drum with a helical groove about its exterior surface, and a drive shaft coupled to the drum to cause the drum to rotate. A roller guide mounted to the lift housing engages the helical groove of the drum such that rotation of the drum causes the drum to translate due to the engagement of the helical groove of the drum with the roller guide. The roller guide can be part of a roller guide assembly that includes a mounting plate and a shaft.Type: GrantFiled: January 11, 2022Date of Patent: November 14, 2023Assignee: Linton Crystal Technologies Corp.Inventors: John A. Reese, Joel C. Stefl
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Patent number: 8951344Abstract: Methods and apparatuses are provided for casting silicon for photovoltaic cells and other applications. With such methods and apparatuses, a cast body of geometrically ordered multi-crystalline silicon may be formed that is free or substantially free of radially-distributed impurities and defects and having at least two dimensions that are each at least about 10 cm is provided.Type: GrantFiled: January 18, 2007Date of Patent: February 10, 2015Assignee: AMG Idealcast Solar CorporationInventor: Nathan G. Stoddard
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Patent number: 8753445Abstract: The invention relates to an apparatus and method for growing a high quality Si single crystal ingot and a Si single crystal ingot and wafer produced thereby. The growth apparatus controls the oxygen concentration of the Si single crystal ingot to various values thereby producing the Si single crystal ingot with high productivity and extremely controlled growth defects.Type: GrantFiled: July 5, 2007Date of Patent: June 17, 2014Assignee: Siltron, Inc.Inventor: Hyon-Jong Cho
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Patent number: 8216372Abstract: The invention relates to an apparatus and method for growing a high quality Si single crystal ingot and a Si single crystal ingot and wafer produced thereby. The growth apparatus controls the oxygen concentration of the Si single crystal ingot to various values thereby producing the Si single crystal ingot with high productivity and extremely controlled growth defects.Type: GrantFiled: February 13, 2006Date of Patent: July 10, 2012Assignee: Siltron Inc.Inventor: Hyon-Jong Cho
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Patent number: 8048221Abstract: Methods and apparatuses are provided for casting silicon for photovoltaic cells and other applications. With such methods and apparatuses, a cast body of monocrystalline silicon may be formed that is free of, or substantially free of, radially-distributed impurities and defects and having at least two dimensions that are each at least about 35 cm is provided.Type: GrantFiled: January 18, 2007Date of Patent: November 1, 2011Inventor: Nathan G. Stoddard
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Patent number: 7799130Abstract: A silicon single crystal ingot growing apparatus for growing a silicon single crystal ingot based on a Czochralski method The silicon single crystal ingot growing apparatus includes a chamber; a crucible provided in the chamber, and for containing a silicon melt; a heater provided at the outside of the crucible and for heating the silicon melt; a pulling unit for ascending a silicon single crystal grown from the silicon melt; and a plurality of magnetic members provided at the outside of the chamber and for asymmetrically applying a magnetic field to the silicon melt Such a structure can uniformly controls an oxygen concentration at a rear portion of a silicon single crystal ingot using asymmetric upper/lower magnetic fields without replacing a hot zone In addition, such a structure can controls a flower phenomenon generated on the growth of the single crystal by the asymmetric magnetic fields without a loss such as the additional hot zone (H/Z) replacement, P/S down, and SR variance.Type: GrantFiled: July 27, 2006Date of Patent: September 21, 2010Assignee: Siltron, Inc.Inventors: Young Ho Hong, Man Seok Kwak, Ill-Soo Choi, Hyon-Jong Cho, Hong Woo Lee
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Patent number: 7758695Abstract: One embodiment of the present invention provides a method for fabricating a high-quality metal substrate. During operation, the method involves cleaning a polished single-crystal substrate. A metal structure of a predetermined thickness is then formed on a polished surface of the single-crystal substrate. The method further involves removing the single-crystal substrate from the metal structure without damaging the metal structure to obtain the high-quality metal substrate, wherein one surface of the metal substrate is a high-quality metal surface which preserves the smoothness and flatness of the polished surface of the single-crystal substrate.Type: GrantFiled: March 2, 2007Date of Patent: July 20, 2010Assignee: Lattice Power (Jiangxi) CorporationInventors: Chuanbing Xiong, Wenqing Fang, Li Wang, Guping Wang, Fengyi Jiang
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Patent number: 7749324Abstract: The present invention includes a method for casting a silicon ingot by using a continuous casting method by means of an electromagnetic induction, and a method for cutting the silicon ingot as a starting material into plural silicon blocks. When the silicon blocks with a square section are cut out, the sectional shape of the silicon ingot is set to be rectangular. Not less than 6 pieces of equal-sized silicon blocks are cut out from the silicon ingot, thereby enabling to enhance the manufacturing efficiency to a great extent. And since the amount of excision of the edge per silicon block is reduced, the production yield can be enhanced. Further, since the proportion of columnar crystals with large grain size inside the ingot can be increased, it becomes possible to enhance the conversion efficiency of a solar battery using the silicon block as a substrate material.Type: GrantFiled: December 21, 2007Date of Patent: July 6, 2010Assignee: Sumco Solar CorporationInventors: Mitsuo Yoshihara, Kenichi Sasatani
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Patent number: 7611580Abstract: System for controlling crystal growth in a Czochralski crystal growing apparatus. A magnetic field is applied within the crystal growing apparatus and varied to control a shape of the melt-solid interface where the ingot is being pulled from the melt. The shape of the melt-solid interface is formed to a desired shape in response to the varied magnetic field as a function of a length of the ingot.Type: GrantFiled: May 25, 2007Date of Patent: November 3, 2009Assignee: MEMC Electronic Materials, Inc.Inventor: Zheng Lu
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Patent number: 7524371Abstract: A method for controlling the temperature gradient on the side surface of a silicon single crystal, the height of a solid-liquid interface, and the oxygen concentration in the longitudinal direction of the silicon single crystal is provided in order to manufacture a defect-free silicon single crystal whose oxygen concentration is controlled to a predetermined value rapidly and stably. By disposing a cylindrical cooler around the silicon single crystal, and adjusting the pulling speed of the silicon single crystal, the rotation speed of a crucible that stores molten silicon and the rotation speed of the silicon single crystal, and the output ratio of a multi-heater separated into at least two in the longitudinal direction of the silicon single crystal disposed around the crucible, the temperature gradient on the side surface, the height of the solid-liquid interface, and the oxygen concentration in the longitudinal direction of the silicon single crystal are controlled.Type: GrantFiled: March 27, 2007Date of Patent: April 28, 2009Assignee: Sumco Techxiv CorporationInventors: Takashi Yokoyama, Toshiaka Saishoji, Toshirou Kotooka, Kazuyoshi Sakatani
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Patent number: 7524375Abstract: The invention provides for growing semiconductor and other crystals by loading a vessel in its lower portion with a seed crystal, loading a charge thereon in the vessel, heating the charge to a molten state and electromagnetically stirring the melt using magnetic and electric fields to obtain a more uniform composition of melt and slowly reducing the temperature of the melt over the crystal to grow a more uniform crystal from such stirred melt.Type: GrantFiled: April 1, 2004Date of Patent: April 28, 2009Assignee: The United States of America as represented by the Secretary of the Air ForceInventors: Gerald W. Iseler, David F. Bliss, Vladimir L. Tassev
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Patent number: 7396406Abstract: A single crystal semiconductor manufacturing method for realizing a dislocation-free single crystal while not varying or hardly varying electric power supplied to a heater when and after a seed crystal comes into contact with a melt. The allowable temperature difference ?Tc not causing dislocation in the seed crystal is determined according to the concentration (C) of the impurities added to the seed crystal (14) and the size (diameter D) of the seed crystal (14). When the seed crystal (14) comes into contact with the melt (5), electric power supplied to a bottom heater (19) is fixed, and a magnetic field produced by a magnet (20) is applied to the melt (5). Electric power supplied to a main heater (9) is controlled so that the temperature at the surface of the melt (5) which the seed crystal (14) comes into contact with may be a target value. After the seed crystal (14) comes into contact with the melt (5), single crystal silicon is pulled up without performing a necking process.Type: GrantFiled: February 9, 2004Date of Patent: July 8, 2008Assignee: Sumco Techxiv CorporationInventors: Hiroshi Inagaki, Masahiro Shibata, Shigeki Kawashima, Nobuyuki Fukuda
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Patent number: 7374614Abstract: The method for manufacturing a single crystal semiconductor achieves an object to reduce the impurity concentration nonuniformity within a semiconductor wafer plane and thus to improve the wafer planarity by introducing an impurity into the single crystal semiconductor more uniformly during the pulling of the single crystal semiconductor from a melt. In the course of pulling the single crystal semiconductor (6), the rotating velocity (?2) of the single crystal semiconductor (6) being pulled is adjusted to a predetermined value or higher, and a magnetic field having a strength in a predetermined range is applied to the melt (5). Particularly, the crystal peripheral velocity is adjusted to 0.126 m/sec or higher, and M/V1/3 is adjusted to 35.5?M/V1/3?61.3. More desirably, the crystal peripheral velocity is adjusted to 0.141 m/sec or higher, and M/V1/3 is adjusted to 40.3?M/V1/3?56.4.Type: GrantFiled: February 18, 2005Date of Patent: May 20, 2008Assignee: Komatsu Denshi Kinzoku Kabushiki KaishaInventors: Masafumi Ura, Hidetoshi Kurogi, Toshiharu Yubitani, Noboru Furuichi
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Patent number: 7371283Abstract: Disclosed is a metod of fabrication of high quality silicon single crystal at high growth rate. The method grows silicon single crystal from silicon melt by Czochralski method, wherein the silicon single crystal is grown according to conditions that the silicon melt has an axial temperature gradient determined according to an equation, {(?Tmax??Tmin)/?Tmin}×100?10, wherein ?Tmax is a maximum axial temperature gradient of the silicon melt and ?Tmin is a minimum axial temperature gradient of the silicon melt, when the axial temperature gradient is measured along an axis parallel to a radial direction of the silicon single crystal.Type: GrantFiled: November 22, 2005Date of Patent: May 13, 2008Assignee: Siltron Inc.Inventor: Hyon-Jong Cho
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Patent number: 7335256Abstract: A silicon single crystal which, over an ingot length of over 10 percent of the total ingot length, has a uniform defect picture and narrow radial dopant and oxygen variations. The process in accordance with the Czochralski method involves bringing about a temperature distribution in the melt in the region of the solidification interface which deviates from rotational symmetry.Type: GrantFiled: July 17, 2006Date of Patent: February 26, 2008Assignee: Siltronic AGInventors: Martin Weber, Wilfried von Ammon, Herbert Schmidt, Janis Virbulis, Yuri Gelfgat, Leonid Gorbunov
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Patent number: 7300518Abstract: The invention provides an apparatus for producing a single crystal, and a method for producing a silicon single crystal using the same. An apparatus for producing a single crystal includes a heating device which heats polycrystalline silicon raw material held in a crucible to form silicon melt, and a pulling up device which grows a silicon single crystal while pulling it up from the silicon melt accompanied with rotation. By providing the apparatus with a magnetic field generation unit which applies to the silicon melt a cusp magnetic field a shape of neutral plane of which is symmetric around the rotation axis of the silicon single crystal and is curved in the upward direction, various conditions for producing a silicon single crystal having a defect free region is relaxed, and a silicon single crystal having a defect free region is produced at high efficiency.Type: GrantFiled: May 18, 2005Date of Patent: November 27, 2007Assignee: Sumco CorporationInventors: Norihito Fukatsu, Kazuyuki Egashira, Senrin Fu
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Patent number: 7291221Abstract: A method and system for use in combination with a crystal growing apparatus for growing a monocrystalline ingot according to a Czochralski process. The crystal growing apparatus has a heated crucible including a semiconductor melt from which the ingot is pulled. The ingot is grown on a seed crystal pulled from the melt. A time varying external magnetic field is imposed on the melt during pulling of the ingot. The magnetic field is selectively adjusted to produce pumping forces in the melt to control a melt flow velocity while the ingot is being pulled from the melt.Type: GrantFiled: December 30, 2004Date of Patent: November 6, 2007Assignee: MEMC Electronic Materials, Inc.Inventor: Harold W Korb
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Patent number: 7282095Abstract: [Problem] A silicon single crystal ingot in which point defect agglomerates do not exist over a substantially entire length thereof is manufactured without reducing a pure margin. [Solving Means] A heat shielding member 36 comprises a bulge portion 41 which is provided to bulge in an in-cylinder direction at a lower portion of a cylindrical portion 37 and has a heat storage member 47 provided therein. A flow quantity of an inert gas flowing down between the bulge portion 41 in the heat shielding member 36 and an ingot 25 when pulling up a top-side ingot 25a of the silicon single crystal ingot 25 is set larger than a flow quantity of the inert gas flowing down between the bulge portion 41 and the ingot 25 when pulling up a bottom-side ingot 25b of the silicon single crystal ingot 25, thereby pulling up the ingot 25.Type: GrantFiled: January 25, 2005Date of Patent: October 16, 2007Assignee: Sumco CorporationInventors: Kazuhiro Harada, Norihito Fukatsu, Senlin Fu, Yoji Suzuki
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Patent number: 7235133Abstract: By utilizing a crystal pulling apparatus for producing a single crystal according to the Czochralski method comprising at least a crucible to be charged with a raw material, a heater surrounding the crucible, and subsidiary heating means provided below the crucible, a single crystal is pulled or the raw material is additionally introduced with heating by the heater surrounding the crucible and the subsidiary heating means when the amount of the raw material melt in the crucible becomes a limited amount. Thus, there is provided a method for growing a single crystal at a high yield while preventing solidification of melt raw material decreased to a limited amount without affecting crystal quality, durability of crucible or the like even when a crucible having a large diameter is used.Type: GrantFiled: February 16, 2001Date of Patent: June 26, 2007Assignee: Shin-Etsu Handotai Co., Ltd.Inventor: Masanori Kimura
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Patent number: 7223304Abstract: Methods and system for controlling crystal growth in a Czochralski crystal growing apparatus. A magnetic field is applied within the crystal growing apparatus and varied to control a shape of the melt-solid interface where the ingot is being pulled from the melt. The shape of the melt-solid interface is formed to a desired shape in response to the varied magnetic field as a function of a length of the ingot.Type: GrantFiled: December 30, 2004Date of Patent: May 29, 2007Assignee: MEMC Electronic Materials, Inc.Inventor: Zheng Lu
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Patent number: 7001459Abstract: A method of making a spinel-structured metal oxide on a substrate by molecular beam epitaxy, comprising the step of supplying activated oxygen, a first metal atom flux, and at least one other metal atom flux to the surface of the substrate, wherein the metal atom fluxes are individually controlled at the substrate so as to grow the spinel-structured metal oxide on the substrate and the metal oxide is substantially in a thermodynamically stable state during the growth of the metal oxide. A particular embodiment of the present invention encompasses a method of making a spinel-structured binary ferrite, including Co ferrite, without the need of a post-growth anneal to obtain the desired equilibrium state.Type: GrantFiled: August 29, 2003Date of Patent: February 21, 2006Assignee: Battelle Memorial InstituteInventor: Scott A. Chambers
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Patent number: 6984264Abstract: A single crystal pulling device is composed of a cylindrical pulling furnace, a crucible disposed in the pulling furnace in which a single crystal material for a semiconductor is poured, a cylindrical vacuum vessel coaxially disposed around the pulling furnace, and a superconducting magnet composed of a plurality pairs of coils arranged inside the vacuum vessel so as to generate magnetic field. The superconducting coils are arranged on the same horizontal plane of the cylindrical vacuum vessel, and each of the paired superconducting coils includes coils set so as to oppose to each other with respect to a central axis of the cylindrical vacuum vessel so that one coil of one pair of coils and one coil of another pair of coils adjacent to that one pair of coils constitutes a set angle, directing towards the inside of the cylindrical vessel, in a range of 100° to 130°.Type: GrantFiled: May 30, 2003Date of Patent: January 10, 2006Assignee: Kabushiki Kaisha ToshibaInventors: Tsutomu Shimonosono, Yoshihiro Koguchi, Takashi Sasaki
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Publication number: 20040107894Abstract: A single crystal pulling device is composed of a cylindrical pulling furnace, a crucible disposed in the pulling furnace in which a single crystal material for a semiconductor is poured, a cylindrical vacuum vessel coaxially disposed around the pulling furnace, and a superconducting magnet composed of a plurality pairs of coils arranged inside the vacuum vessel so as to generate magnetic field. The superconducting coils are arranged on the same horizontal plane of the cylindrical vacuum vessel, and each of the paired superconducting coils includes coils set so as to oppose to each other with respect to a central axis of the cylindrical vacuum vessel so that one coil of one pair of coils and one coil of another pair of coils adjacent to that one pair of coils constitutes a set angle, directing towards the inside of the cylindrical vessel, in a range of 100° to 130°.Type: ApplicationFiled: May 30, 2003Publication date: June 10, 2004Applicant: KABUSHIKI KAISHA TOSHIBA, Tokyo, JapanInventors: Tsutomu Shimonosono, Yoshihiro Koguchi, Takashi Sasaki
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Patent number: 6592662Abstract: In a method manufacturing a silicon single crystal 8 according to an MCZ method, a flow rate of an inert gas flowing in a growth furnace 1 during growth of the silicon single crystal 8 and/or a pressure in the growth furnace 1 is altered according to a pulling amount of the silicon single crystal 8 to adjust an interstitial oxygen concentration therein. By altering a flow rate of an inert gas flowing in the growth furnace or a pressure therein, an amount of oxygen evaporating as an oxide from a surface of a silicon melt 10 in the vicinity of a crystal growth interface can be easily adjusted, and thereby, an oxygen amount included in the silicon melt 10 can be controlled with ease.Type: GrantFiled: October 24, 2001Date of Patent: July 15, 2003Assignee: Shin-Etsu Handotai Co., Ltd.Inventors: Izumi Fusegawa, Ryoji Hoshi, Kouichi Inokoshi, Tomohiko Ohta
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Patent number: 6579363Abstract: By using a semiconductor single crystal pulling apparatus for growing single crystals by the Czochralski method while rotating the melt by a magnetic field and electric current, namely by the EMCZ method, which comprises a main pulling means for pulling a single crystal, a holding mechanism for gripping an engaging stepped portion formed on the single crystal through engaging members and a sub pulling means for moving the holding mechanism up and down and in which an electric current is passed through the main pulling means and through the sub pulling means, it is possible to prevent heavy single crystals from undergoing a falling accident and, at the same time, effectively reduce the power consumption. In this pulling apparatus, it is effective to feed an electric current to the sub pulling means alone and it is desirable to dispose two or more electrodes whether the pulling means is of a shaft type or wire type.Type: GrantFiled: October 17, 2001Date of Patent: June 17, 2003Assignees: Sumitomo Metal Industries, Ltd., NEC CorporationInventors: Souroku Kawanishi, Masahito Watanabe, Minoru Eguchi
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Patent number: 6554895Abstract: A method for manufacturing a solid single crystal of an electrically conductive material by pulling from a molten mass of this material, the material presenting atom clusters at melt. The method includes: a melt stage so as to obtain a molten mass, the melt stage procuring a colder zone of the molten mass, from which the single crystal will be pulled, and a hotter zone having sufficient temperature to melt the atom clusters; a stage of application to the molten mass of a rotating magnetic field allowing the atom clusters to be displaced from the colder zone to the hotter zone; and a stage of growth by pulling of the single crystal after the atom clusters have been displaced from the colder zone to the hotter zone.Type: GrantFiled: June 19, 2001Date of Patent: April 29, 2003Assignee: Comissariat a l'Energie AtomiqueInventors: Thierry Duffar, Jean-Paul Garandet
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Patent number: 6535092Abstract: A device (1) for generating a variable composite magnetic field comprises top and bottom concentric ring members (3, 4) which define a main central axis (5) and a central area (4) within which the composite magnetic filed is formed. Rod-like permanent magnets are located thin respective annuli (15) of the respective ring members (2, 3), and are equi-spaced circumferentially along a pitched circle (21). The permanent magnets (18) are rotable about corresponding secondary axes (19) which extend parallel to each other and parallel to the main central axis (5). The permanent magnets (18) are magnetised with their respective direction of magnetisation extending transversely of their secondary axes (19) and are independently rotatable by corresponding stepper motors (22) in respective of annuli (16) of the ring members (2, 3) for orienting the permanent magnets (18) about their respective secondary axes (19) for in turn altering the composite magnetic field generated in the central area (4).Type: GrantFiled: June 20, 2002Date of Patent: March 18, 2003Assignee: Magnetic Solutions (Holdings) LimitedInventors: David Patrick Hurley, John Michael David Coey
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Patent number: 6527852Abstract: A semiconductor crystal growing apparatus includes a device for applying a magnetic field to inside a semiconductor melt and a device for passing a current through the semiconductor melt. An electrode for applying the current to the inside of the semiconductor melt extends through a tube surrounding the electrode.Type: GrantFiled: April 18, 2001Date of Patent: March 4, 2003Assignee: NEC CorporationInventors: Masahito Watanabe, Minoru Eguchi
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Publication number: 20030010282Abstract: An apparatus and method is provided for manufacturing a semiconductor substrate such as web crystals. The apparatus includes a chamber and a growth hardware assembly housed within the chamber. A magnetic field system produces a vertical magnetic field within the chamber.Type: ApplicationFiled: August 2, 2002Publication date: January 16, 2003Inventors: Hilton F. Glavish, Hideyuki Isozaki, Keiji Maishigi, Kentaro Fujita
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Patent number: 6497761Abstract: An apparatus for growing a single crystal of semiconductor is provided, which makes it possible to grow a heavy single crystal of semiconductor of 100 kg or greater in weight even if a growing single crystal contains a neck. In the apparatus, the first and second electrodes are provided such that the first ends of the first and second electrodes are electrically connected to the power supply and the second ends of the first and second electrodes are contacted with the melt in the crucible. During the growth process, a specific voltage is applied across the first ends of the first and second electrodes, thereby forming the electrical current path interconnecting the second ends of the first and second electrodes in the melt. The magnetic field is generated with the magnetic field generator to intersect with the electrical current path in the melt. No electric current flows through the growing single crystal from the melt.Type: GrantFiled: March 6, 2001Date of Patent: December 24, 2002Assignee: NEC CorporationInventors: Masahito Watanabe, Minoru Eguchi
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Patent number: 6433661Abstract: A magnetic-field thermal treatment apparatus is used to carry out a thermal treatment for plural substrates, which are placed in a vacuum chamber, as a magnetic field is applied to the substrates. Around the vacuum chamber, a heater and a solenoid type cryocooler-cooled superconductive magnet unit as a magnetic field generating unit are provided. The substrates held in a substrate holder are retained in the interior of the vacuum chamber so that the surfaces of the substrates become parallel to one another in a vertical direction. The superconductive magnet unit has at least one superconductive coil surrounding the vacuum chamber horizontally so as to exert the magnetic field, which is parallel to the surfaces of the substrates, on the substrates.Type: GrantFiled: September 21, 2000Date of Patent: August 13, 2002Assignees: Sumitomo Heavy Industries, Ltd., Futek Furnace Inc.Inventors: Junichi Mita, Kazuhito Yamamoto, Hiroto Ueno
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Patent number: 6423285Abstract: In a method for producing a silicon single crystal by growing a single crystal ingot while a magnetic field perpendicular to a crystal growth axis is applied to a silicon melt contained in a quartz crucible during pulling of the single crystal from the melt contained in the quartz crucible, the crystal growth is performed so that one of a low temperature region and a high temperature region generated at a surface of the silicon melt contained in the crucible should always cover a solid-liquid interface of the crystal growth, or a ratio of vertical magnetic field component to horizontal magnetic field component for magnetic field strength at the crystal center of the surface of the silicon melt contained in the quartz crucible is controlled to be 0.3 or more and 0.5 or less.Type: GrantFiled: November 7, 2000Date of Patent: July 23, 2002Assignee: Shin-Etsu Handotai Co., Ltd.Inventors: Kirio Itoi, Eiichi Iino, Tohru Ishizuka, Tomohiko Ohta, Izumi Fusegawa
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Patent number: 6387466Abstract: The high quality silicon wafer of large diameter is invented by mainly paying attention to the particles ascribed to the crystal and the wafer is optimal for manufacturing ultra highly integrated devices. The silicon wafer is of diameter of 300 mm and larger sliced from a single-crystal silicon ingot pulled by CZ method, the surface is mirror-polished and cleaned with ammonia based cleaning solution, and the number of particles of 0.083 &mgr;m and larger in size detected on its main surface is 120 and smaller and/or particles of 0.090 &mgr;m and larger in size is smaller than 80.Type: GrantFiled: October 28, 1999Date of Patent: May 14, 2002Assignee: Shin-Etsu Handotai Co., Ltd.Inventors: Izumi Fusegawa, Masakazu Sato
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Patent number: 6267816Abstract: This is a method for growing by pulling single crystals 6 using CZ process from material melt 5 to which cusp magnetic field is applied. Inside diameter U of the crucible 3 that contains the material melt 5 is (Y+140 mm) or larger and less than 3Y, where Y stands for outside diameter of the single crystal 6. When cusp magnetic field is applied, high pulling yield is maintained even if the inside diameter U of the crucible is small. Oxygen yield and dislocation free yield are improved by reducing inside diameter U of the crucible. As a result, the yield of manufacturing single crystals 6 is improved.Type: GrantFiled: March 23, 1999Date of Patent: July 31, 2001Assignee: Sumitomo Sitix CorporationInventor: Teruo Izumi
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Patent number: 6261361Abstract: There is disclosed a method for producing a silicon single crystal wafer wherein a silicon single crystal is grown in accordance with the CZ method with doping nitrogen in an N-region in a defect distribution chart which shows a defect distribution in which the horizontal axis represents a radial distance D (mm) from the center of the crystal and the vertical axis represent a value of F/G (mm2/° C.·min), where F is a pulling rate (mm/min) of the single crystal, and G is an average intra-crystal temperature gradient(° C./mm) along the pulling direction within a temperature range of the melting point of silicon to 1400° C. There can be provided a method of producing a silicon single crystal wafer consisting of N-region where neither V-rich region nor I-rich region is present in the entire surface of the crystal by CZ method, under the condition that can be controlled easily in a wide range, in high yield, and in high productivity.Type: GrantFiled: May 19, 2000Date of Patent: July 17, 2001Assignee: Shin-Etsu Handotai Co., Ltd.Inventors: Makoto Iida, Masaro Tamatsuka, Masanori Kimura, Shozo Muraoka
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Patent number: 6221156Abstract: In an apparatus for growing a semiconductor crystal from semiconductor melt, a crucible retains the semiconductor melt. An electrode contacts with the semiconductor melt and applies current to the semiconductor melt. The electrode is formed of the same material as the semiconductor crystal.Type: GrantFiled: March 15, 1999Date of Patent: April 24, 2001Assignee: NEC CorporationInventors: Masahito Watanabe, Minoru Eguchi
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Patent number: 6200384Abstract: In the growth of a large silicon single crystal weighing not less than 100 kg by the Czokralski method resorting to application of a magnetic field, a crucible, not less than 0.7 m in inside diameter is used, and a cusped magnetic field which manifests a maximum intensity of not more than 1000 gausses on the inner wall of the crucible is applied.Type: GrantFiled: July 27, 1999Date of Patent: March 13, 2001Assignee: Nippon Steel CorporationInventors: Yutaka Kishida, Wataru Ohashi, Teruyuki Tamaki, Seiki Takebayashi
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Patent number: 6190452Abstract: There is disclosed a method for producing a silicon single crystal in accordance with the Czochralski method wherein a crystal is pulled with controlling a temperature in a furnace so that &Dgr;G may be 0 or a negative value, where &Dgr;G is a difference between the temperature gradient Gc (° C./mm) at the center of a crystal and the temperature gradient Ge (° C./mm) at the circumferential portion of the crystal, namely &Dgr;G=(Ge−Gc), wherein G is a temperature gradient in the vicinity of a solid-liquid interface of a crystal from the melting point of silicon to 1400° C.Type: GrantFiled: June 8, 1999Date of Patent: February 20, 2001Assignee: Shin-Etsu Handotai Co., Ltd.Inventors: Masahiro Sakurada, Hideki Yamanaka, Tomohiko Ohta
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Patent number: 6159438Abstract: In method for manufacturing a silicon single crystal in accordance with a Czochralski method, during the growth of the silicon single crystal, pulling is performed such that a solid-liquid interface in the crystal, excluding a peripheral 5 mm-width portion, exists within a range of an average vertical position of the solid-liquid interface.+-. 5 mm. There is also disclosed a method for manufacturing a silicon single crystal in accordance with the Czochralski method, wherein during the growth of a silicon single crystal, a furnace temperature is controlled such that a temperature gradient difference .DELTA.G (=Ge-Gc) is not greater than 5.degree. C./cm, where Ge is a temperature gradient (.degree. C./cm) at a peripheral portion of the crystal, and Gc is a temperature gradient (.degree. C./cm) at a central portion of the crystal, both in an in-crystal descending temperature zone between 1420.degree. C. and 1350.degree. C. or between a melting point of silicon and 1400.degree. C.Type: GrantFiled: July 22, 1999Date of Patent: December 12, 2000Assignee: Shin-Etsu Handotai Co., Ltd.Inventors: Makoto Iida, Eiichi Iino, Masanori Kimura, Shozo Muraoka, Hideki Yamanaka
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Patent number: 6156119Abstract: In a method for producing a silicon single crystal of high quality, the silicon single crystal is grown based on a magnetic field applied Czochralski method. The single crystal is grown at a high growth rate satisfying the equation Vave.gtoreq.120/r, where Vave denotes an average crystal growth rate, and r denotes a radius of the single crystal, and a rotation number R of the single crystal in growing satisfies the equation R.ltoreq.1250/r. Oxygen concentration in-plane distribution is 10% or less, and a deformation ratio of a constant diameter portion in the silicon single crystal in a direction perpendicular to a crystal growth axis direction is 5% or less. The silicon single crystal has a high uniformity of oxygen concentration in-plane distribution without deformation of crystal, even if the crystal is grown at a growth rate exceeding the upper limits found in conventional techniques.Type: GrantFiled: March 17, 1999Date of Patent: December 5, 2000Assignee: Shin-etsu Handotai Co., Ltd.Inventors: Ryoji Hoshi, Kouichi Inokoshi, Tomohiko Ohta
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Patent number: 6113688Abstract: A method of growing a single crystal, comprises pulling a single crystal from molten material in a crucible by the Czochralski method; simultaneously applying an axially symmetric, radial cusp magnetic field to the molten material; and simultaneously heating the crucible from both the bottom and the sides; where a ratio of the heating from the bottom of the crucible, q, to the total heating of the crucible, Q, is q/Q, and during the pulling the ratio q/Q changes. The concentration of oxygen in the pulling direction of the crystal may be accurately controlled, and is uniform.Type: GrantFiled: October 1, 1998Date of Patent: September 5, 2000Assignee: Sumitomo Metal Industries, Ltd.Inventors: Souroku Kawanishi, Makoto Itou
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Patent number: 6086671Abstract: A method for melting a silicon starting material can suppress silica (SiO2) from melting out from a quartz crucible wherein the silicon starting material is melted and can provide a high-quality silicon single crystal in a high yield. The growth method comprises melting the silicon starting material charged in the crucible while applying thereto a static magnetic field, contacting a seed crystal to a surface of the silicon melt, and pulling the seed crystal upwardly to solidify the contacted melt. The silicon starting material charged in the crucible, which is under melting, is applied with a static magnetic field such as a Cusp magnetic field, a horizontal magnetic field and/or a vertical magnetic field. The application can control heat convection occurring in the crucible during the course of the melting of the starting material, thereby obtaining a silicon single crystal having a reduced number of dislocation defects.Type: GrantFiled: September 1, 1998Date of Patent: July 11, 2000Assignee: Sumitomo Sitix CorporationInventors: Souroku Kawanishi, Youichi Yamamoto
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Patent number: 6077346Abstract: In the growth of a semiconductor single crystal according to the Czochralski method, a magnetic field is generated in a semiconductor melt and a current is supplied in the semiconductor melt in a direction perpendicular to the magnetic field. This makes it possible to cause the semiconductor melt to rotate spontaneously without rotating the crucible, thereby to grow a single crystal of semiconductor without striation even when growing a single crystal of semiconductor having a large diameter. Also it is made possible to exactly control the rotation rate of the semiconductor melt by changing the intensity of the magnetic field and the magnitude of the current independently. Further, the distribution of the rotation rates in the semiconductor melt can also be varied by changing the position of electrodes or electrode protecting tubes for immersing in the semiconductor melt.Type: GrantFiled: December 11, 1998Date of Patent: June 20, 2000Assignee: NEC CorporationInventors: Masahito Watanabe, Minoru Eguchi
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Patent number: 6060971Abstract: The present invention provides a superconducting magnet device for a crystal pulling device comprising a pair of ring-like superconducting coils facing with each other, with the crystal pulling device disposed therebetween, a radiation shield surrounding the superconducting coils, and a vessel surrounding the radiation shield, wherein the vessel on the side facing to the crystal pulling device is made from a nonmagnetic substance, and the vessel on the other side is made from a magnetic substance.Type: GrantFiled: February 16, 1999Date of Patent: May 9, 2000Assignee: Kabushiki Kaisha ToshibaInventors: Takashi Sasaki, Masanori Arata
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Patent number: 6019837Abstract: A temperature sensor 42 is provided in a furnace 11, measuring temperature above a molten liquid 24 put in a crucible 12 to check proceedings of evaporation of oxygen vaporized from a free surface 44 of the molten liquid 24. From the data, and considering the relation with the oxygen dissolved into the crucible 12, the oxygen concentration in the molten liquid 24 can be found and the amount of oxygen taken into a single silicon crystal 40 pulled up from the molten liquid 24 can be figured out.Type: GrantFiled: November 25, 1997Date of Patent: February 1, 2000Assignees: Komatsu Electronic Metals Co., Ltd., Mitsubishi Materials Silicon Corporation, Kagaku Gijutsu Sinkou Jigyo Dan, Toshiba Ceramics Co., Ltd.Inventors: Susumu Maeda, Keisei Abe, Kazutaka Terashima, Hideo Nakanishi
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Patent number: 6007625Abstract: This invention provides a method and a apparatus capable of manufacturing single crystals with an oxygen density of less than 12.times.10.sup.17 atoms/cm.sup.3 or less than 10.times.10.sup.17 atoms/cm.sup.3, and wherein the oxygen density of the single crystal produced is uniformly distributed along its longitudinal axis. The electrical power inputted into the main heater 6 surrounding the quartz crucible 4 and the top heater 9 shaped like a reverse frustrated cone and disposed above the quartz crucible 4, is controlled to keep the temperature of the melt 5 in a preset range during the process of pulling up the single crystal silicon 10. When combining the main heater 6 and the top heater 9, the heat emitted from the main heater 6 can be kept small, and the heat load on the quartz crucible 4 and the amount of oxygen released from the quartz crucible 4 and dissloved into melt 5 can be reduced.Type: GrantFiled: September 30, 1997Date of Patent: December 28, 1999Assignee: Komatsu Electronic Metals Co., Ltd.Inventors: Junsuke Tomioka, Hiroshi Inagaki, Fumitaka Ishikawa
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Patent number: 6001170Abstract: A process for the growth of a single crystal from semiconductor material by the Czochralski method, in which the melt is subjected to the influence of a magnetic field during the crystal growth and the magnetic field is generated by superposing a static magnetic field and an alternating magnetic field. An apparatus for carrying out the process, has a magnetic means which comprises two coils which are arranged around a crucible, one coil generating a static magnetic field and the other coil generating an alternating magnetic field.Type: GrantFiled: August 9, 1996Date of Patent: December 14, 1999Assignee: Wacker Siltronik Gesellschaft fur Halbleitermaterialien AGInventors: Erich Tomzig, Werner Zulehner, Wilfried Von Ammon, Yu M Gelfgat, Leonid Gorbunov