Having Pulling During Growth (e.g., Czochralski Method, Zone Drawing) Patents (Class 117/13)
  • Patent number: 7083677
    Abstract: Using a seed crystal comprising a silicon single crystal not including a vacancy excess region, a neck comprising a silicon single crystal not including a vacancy excess region is grown with a diameter contracted smaller than, or equal to that of the contact surface of the silicon seed crystal in contact with a raw material silicon melt, and necking is performed so that the length L of the neck satisfies L?d·(cot ?), where d denotes the length of the diameter or the diagonal of the contact surface of the silicon seed crystal in contact with the raw material silicon melt, and ? denotes the angle formed between the propagation direction of dislocations and the growth direction of the neck, and then the silicon single crystal is grown with the diameter expanded.
    Type: Grant
    Filed: August 19, 2004
    Date of Patent: August 1, 2006
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventor: Masayuki Watanabe
  • Patent number: 7081422
    Abstract: There are provided a heat-treating method capable of suppressing generation of slip in a CZ silicon single crystal wafer having a diameter of mainly 300 mm or more even under high temperature heat treatment to annihilate grown-in defects in the vicinity of a surface of the wafer, and an annealed wafer having a DZ layer in a surface layer of the wafer and oxide precipitates in the bulk thereof at a high density which exert a high gettering effect. First heat treatment of a silicon single crystal wafer manufactured from a silicon single crystal ingot pulled by means of a Czochralski method is performed at a temperature in the range of 600 to 1100° C. to form oxide precipitates in the bulk of the wafer, and thereafter, second heat treatment is performed at a temperature in the range of 1150 to 1300° C.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: July 25, 2006
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Yoshinori Hayamizu, Satoshi Tobe, Norihiro Kobayashi
  • Patent number: 7074271
    Abstract: A surface of a reference sample is contaminated with a transition metal, and a heat treatment is performed to diffuse the transition metal in the sample. A concentration of recombination centers formed by the transition metal is measured in the entire heat-treated reference sample, and a region [V], a region [Pv], a region [Pi], and a region [I] in the reference sample are defined based on the values measured. Meanwhile, recombination lifetimes associated with the transition metal are measured in the entire heat-treated reference sample. Based on both of the measurement results, a correlation line of the concentration of recombination centers and the recombination lifetimes is produced. A surface of the measurement sample is contaminated with the transition metal, and a heat treatment is performed to diffuse the transition metal in the sample.
    Type: Grant
    Filed: February 23, 2004
    Date of Patent: July 11, 2006
    Assignee: Sumitomo Mitsubishi Silicon Corporation
    Inventors: Jun Furukawa, Kazunari Kurita, Kazuhiro Harada
  • Patent number: 7070649
    Abstract: A process for producing a doped silicon single crystal, comprising after-doping the melt during the pulling process with a quantity of volatile dopant ?N(t), calculated according to the equation ?N(t)=N0?N(t)=N0·(1?e??a·t) or according to the approximation equation ?N(t)=N0·?a·t where ?a is an evaporation coefficient which describes process-specific evaporation behavior of the foreign substance and which is obtained after a resistance profile R(t) of a further single crystal has been measured and calculated according to the equation R(t)=R0·e?a·t, where R0 is a starting resistivity and the further single crystal is pulled under the same process conditions without being after-doped with the foreign substance.
    Type: Grant
    Filed: October 21, 2003
    Date of Patent: July 4, 2006
    Assignee: Siltronic AG
    Inventors: Martin Weber, Peter Vilzmann, Erich Gmeilbauer, Robert Vorbuchner
  • Patent number: 7067007
    Abstract: The process for growing single crystals, wherein crystal material is melted in a crucible and a crystal nucleus is immersed in the molten crystal material and slowly pulled out, wherein the crystal formed during the pulling is kept at a temperature close to melting temperature of the output material. The invention also includes a device for practicing the above process.
    Type: Grant
    Filed: August 22, 2003
    Date of Patent: June 27, 2006
    Assignee: Schott Glas
    Inventors: Lothar Ackermann, Daniel Rytz, Klaus Dupre
  • Patent number: 7048796
    Abstract: At the time of fabricating a silicon single crystal wafer from a nitrogen-doped silicon single crystal grown according to the Czochralski method, a silicon single crystal wafer covered with a region in which an oxygen precipitation bulk micro defect and an oxidation induced stacking fault mixedly exist is subjected to heat treatment at a temperature of 1100 to 1300° C. in a reducing gas or inert gas atmosphere. In such a manner, a method of fabricating a high-quality silicon single crystal wafer and a silicon single crystal wafer in which no grown-in crystal defects exist in the whole surface and oxygen precipitation bulk micro defects (BMD) are formed at a sufficiently high density to display the IG effect on the inner side can be provided. The single crystal wafer can be suitably used to form an operation region of a semiconductor device.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: May 23, 2006
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Masayuki Watanabe, Junichi Osanai, Akihiko Kobayashi, Kazuhiko Kashima, Hiroyuki Fujimori
  • Patent number: 7022180
    Abstract: Methods and apparatus for concurrent growth of multiple crystalline ribbons from a single crucible employ meniscus shapers to facilitate continuous growth of discrete and substantially flat crystalline ribbons having controlled width.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: April 4, 2006
    Assignee: Evergreen Solar, Inc.
    Inventor: Richard Lee Wallace, Jr.
  • Patent number: 7014704
    Abstract: A method for growing a silicon single crystal used for semiconductor integrated circuit devices, wherein the single crystal is grown by the CZ method at a nitrogen concentration of 1×1013 atoms/cm3–1×1015 atoms/cm3 with a cooling rate of not less than 2.5° C./min at a crystal temperature of 1150° C.–1000° C., in which case, the pulling rate is adjusted such that the outside diameter of a circular region including oxidation-induced stacking faults generated at the center of a wafer which is subjected to the oxidation heat treatment at high temperature is not more than ? of the wafer diameter, wherein the wafer is prepared by slicing the grown single crystal. In the growth method, the concentration of oxygen in the silicon single crystal is preferably not more than 9×1017 atoms/cm3 (ASTM '79). With this method, the silicon single crystal, in which the generation of Grown-in defects can be effectively suppressed, can be produced in a simple process without any increase in the production cost.
    Type: Grant
    Filed: June 6, 2003
    Date of Patent: March 21, 2006
    Assignee: Sumitomo Mitsubishi Silicon Corporation
    Inventors: Toshiaki Ono, Tadami Tanaka, Shigeru Umeno, Eiichi Asayama, Hideshi Nishikawa
  • Patent number: 6997986
    Abstract: A method for preparing a high-quality garnet single crystal represented by the composition formula CaxNbyGazO12 (2.9<x<3.1, 1.6<y<1.8, 3.1<z<3.3) is provided. The single crystal can preferably be used as a single crystal substrate for forming a defect-free single crystal of bismuth-substituted rare-earth iron garnet thereon by liquid-phase epitaxial deposition. The method is to prepare a single crystal by the Czochralski technique, the single crystal having a garnet structure being represented by the composition formula CaxNbyGazO12 (2.9<x<3.1, 1.6<y<1.8, 3.1<z<3.3). The crystal is grown at a crystal growth rate g less than or equal to 1.72 mm/h. The crystal is preferably grown in an atmosphere containing oxygen 0.4% or more by volume and below 10.0% by volume.
    Type: Grant
    Filed: January 8, 2004
    Date of Patent: February 14, 2006
    Assignee: TDK Corporation
    Inventor: Jun Sato
  • Patent number: 6994747
    Abstract: An optical member manufacturing method of the present invention has a growth step of growing an ingot of a fluoride crystal, a plane orientation measurement step of measuring two or more crystal plane orientations of the ingot, a cutout step of cutting out an optical material from the ingot along any one of the crystal plane orientations obtained in the plane orientation measurement step, and a machining step of performing predetermined machining processing on the optical material to obtain an optical member.
    Type: Grant
    Filed: July 17, 2002
    Date of Patent: February 7, 2006
    Assignee: Nikon Corporation
    Inventors: Hiroyuki Hiraiwa, Shigeru Sakuma, Minako Azumi, Masaaki Mochida
  • Patent number: 6994748
    Abstract: A melt level or the gap between a melt surface and a heat shield is measured accurately irrespective of how the melt surface is. A laser beam from a range-finding unit is reflected by a scanning mirror and projected on a melt surface through an entrance window and a quartz prism in a chamber of a puller. After specular reflection, the beam forms a measurement spot in the bottom of a heat shield and scatters. Part of the scatter, after specular reflection at the melt surface (secondary reflection), passes through the prism, the entrance window and the scanning mirror to the range-finding unit. The range-finding unit carries out triangulation using the distance between a laser source and a photodetector therein, and the angle of incidence and the angle of the received laser beam.
    Type: Grant
    Filed: May 1, 2001
    Date of Patent: February 7, 2006
    Assignee: Komatsu Denshi Kinzoku Kabushiki Kaisha
    Inventors: Masato Moriya, Tadayuki Hanamoto, Hiroshi Monden, Toshio Hayashida, Toshirou Kotooka
  • Patent number: 6986925
    Abstract: A single crystal silicon wafer comprising a front surface, a back surface, a lateral surface joining the front and back surfaces, a central axis perpendicular to the front and back surfaces, and a segment which is axially symmetric about the central axis extending substantially from the front surface to the back surface in which crystal lattice vacancies are the predominant intrinsic point defect, the segment having a radial width of at least about 25% of the radius and containing agglomerated vacancy defects and a residual concentration of crystal lattice vacancies wherein (i) the agglomerated vacancy defects have a radius of less than about 70 nm and (ii) the residual concentration of crystal lattice vacancy intrinsic point defects is less than the threshold concentration at which uncontrolled oxygen precipitation occurs upon subjecting the wafer to an oxygen precipitation heat treatment.
    Type: Grant
    Filed: January 2, 2002
    Date of Patent: January 17, 2006
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Robert J. Falster, Vladimir V. Voronkov, Paolo Mutti, Francesco Bonoli
  • Patent number: 6960254
    Abstract: A method and apparatus for controlling the quenching rate of a monocrystalline ingot pulled from a melt by adjusting one or more post growth processing parameter. A temperature model generates a temperature profile that represents the surface temperature along the length of the ingot at the instant it is pulled from the melt. A first temperature at a particular location along the length of the crystal is determined from the temperature profile. A temperature sensor senses a second temperature at the same particular location. A PLC calculates a quenching rate of the crystal as a function of the first temperature and the second temperature. The PLC generates an error between a target quenching rate and a calculated quenching rate, and one or more post growth process parameters are adjusted as function of the error signal to optimize the quenching rate.
    Type: Grant
    Filed: July 21, 2003
    Date of Patent: November 1, 2005
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Zheng Lu, Steven L. Kimbel
  • Patent number: 6951585
    Abstract: A liquid-phase growth method for immersing a polycrystalline substrate in a melt in a crucible wherein crystal ingredients are dissolved, thereby growing poly crystals upon the substrate, comprises a first step for growing poly crystals to a predetermined thickness, and a second step for melting back a part of the poly crystals grown in the first step in the melt, wherein the relative position between the substrate and melt is changed between the first step and second step, bringing melt with different temperature into contact with the polycrystalline surface. The obtained poly crystals have properties rivaling those of poly crystals used in conventional solar cells but with little risk of trouble such as line breakage of grid electrodes in application to solar cells, and can be obtained in great quantities at low costs.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: October 4, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsumi Nakagawa, Shunichi Ishihara, Hiroshi Sato, Shoji Nishida, Yasuyoshi Takai
  • Patent number: 6926771
    Abstract: A method for growing stoichiometric lithium niobate and lithium tantalate single crystals is provided. A crystal growing apparatus that includes a long crucible with a separation member therein is used. A solid feed material is quenched from a molten state, solidified in batches or sintered before charged in the long crucible to obtain substantially stoichiometric solids. The separation member divides the long crucible into a melting zone and a feeding zone located under the melting zone, and it could effectively prevent bubble formation in the growing crystal. The stoichiometry of the axial and radial composition can be well controlled, and the control of the diameter of the crystal body is easily achieved as well.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: August 9, 2005
    Assignee: National Taiwan University
    Inventor: Chung-Wen Lan
  • Patent number: 6916370
    Abstract: An object of the invention is to provide a quartz glass crucible for pulling up silicon single crystal and a method for producing the same, suitable for improving the productivity of the crucible and the quality of the silicon single crystal, which, by forming a crystalline layer on the inner surface of the quartz glass crucible during pulling up silicon single crystal, prevents degradation from occurring on the inner surface of the crucible and increases the ratio of single crystal while preventing the dislocation from forming on the single crystals.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: July 12, 2005
    Assignees: Heraeus Quarzglas GmbH & Co. KG, Shin-Etsu Quartz Products Co. Ltd.
    Inventor: Hiroyuki Watanabe
  • Patent number: 6913646
    Abstract: There can be provided a silicon single crystal wafer grown according to Czochralski method wherein the whole plane of the wafer is occupied by N region on the outside of OSF generated in a shape of a ring by thermal oxidation treatment and there exists no defect region detected by Cu deposition. Thereby, there can be produced a silicon single crystal wafer according to CZ method, which does not belong to any of V region rich in vacancies, OSF region and I region rich in interstitial silicons, and can surely improve electric characteristics such as oxide dielectric breakdown voltage characteristics or the like under stable manufacture conditions.
    Type: Grant
    Filed: December 26, 2001
    Date of Patent: July 5, 2005
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Masahiro Sakurada, Takeshi Kobayashi, Tatsuo Mori, Izumi Fusegawa, Tomohiko Ohta
  • Patent number: 6913647
    Abstract: A process for producing silicon which is substantially free of agglomerated intrinsic point defects in an ingot having a vacancy dominated region. An ingot is grown generally in accordance with the Czochralski method. While intrinsic point defects diffuse from or are annihilated within the ingot, at least a portion of the ingot is maintained above a temperature TA at which intrinsic point defects agglomerate. The achievement of defect free silicon is thus substantially decoupled from process parameters, such as pull rate, and system parameters, such as axial temperature gradient in the ingot.
    Type: Grant
    Filed: May 13, 2003
    Date of Patent: July 5, 2005
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Robert J. Falster, Harold W. Korb
  • Patent number: 6911080
    Abstract: A evaluation process of a vibration level at the surface of silicon melt held in a silica glass crucible is provided by setting in the vacuum furnace, the test piece of the silica glass cut out from a silica glass crucible, melting a little amount of silicon put on said piece of the glass, and measuring a vibration cycle of the silicon melt. Moreover, a silica glass crucible not causing the vibration at the surface of the silicon melt held in the silica glass crucible is also provided, wherein the vibration cycle of a silica glass of a side wall of the crucible is controlled at more than ? seconds.
    Type: Grant
    Filed: October 10, 2003
    Date of Patent: June 28, 2005
    Assignee: Japan Super Quartz Corporation
    Inventors: Hiroshi Kishi, Minoru Kanda, Masanori Fukui
  • Patent number: 6908509
    Abstract: Additional charge of a solid raw material 13 in the shapes of granules/lumps, low in raw material cost, and with no risk of cracking, is performed into a molten raw material 14 in a crucible in a static manner without solidifying a surface of the molten raw material 14 in the crucible 3. A bottom of a cylindrical raw material vessel 10 made of a material non-meltable when being in contact with the molten raw material 14 in the crucible 3 is closed with a bottom cover 11 made of a material meltable and removable when being in contact with the molten raw material 14 in the crucible 3. The raw material vessel 10 in a state of being filled with the solid raw material 13 in the shapes of granules/lumps is hung down above the crucible 3 to immerse the lower portion thereof into the molten raw material 14 in the crucible 3.
    Type: Grant
    Filed: August 25, 2003
    Date of Patent: June 21, 2005
    Assignee: Sumitomo Mitsubishi Silicon Corporation
    Inventors: Katsunori Nakashima, Makoto Ito
  • Patent number: 6902618
    Abstract: The present invention provides a silicon single crystal wafer having a diameter of 300 mm or more and having a defect-free layer containing no COP for a depth of 3 ?m or more from a surface and a method for producing a silicon single crystal, wherein, when a silicon single crystal having a diameter of 300 mm or more is pulled with nitrogen doping by the CZ method, the crystal is grown with a value of V/G [mm2/K·min] of 0.17 or less, where V [mm/min] is a pulling rate, and G [K/mm] is an average of temperature gradient in the crystal along a pulling axis from the melting point of silicon to 1400° C. Thus, there are established conditions for pulling a silicon single crystal and conditions for heat treatment of wafer for obtaining a silicon single crystal wafer having a defect-free layer free from COP for a sufficient depth of the surface layer by pulling a silicon single crystal having a diameter of 300 mm or more, processing the crystal into wafers and subjecting the wafers to the heat treatment.
    Type: Grant
    Filed: June 7, 2002
    Date of Patent: June 7, 2005
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventor: Makoto Iida
  • Patent number: 6899759
    Abstract: A single crystal production method based on the Czochralski method comprises controlling a number of crucible rotations and crystal rotations so that a number of vibrations for driving a melt, determined on the basis of the number of crucible and crystal rotations during a single crystal growing procedure, is outside a range from 95% to 105% of a number of sloshing resonance vibrations of the melt. In another embodiment, the method comprises controlling a number of rotations of a crystal and crucible, so that when a number of vibrations for driving a melt, determined by the number of crucible and crystal rotations during a single crystal growing procedure, is within a range from 95% to 105% of a number of sloshing resonance vibrations of the melt, the number of vibrations of the melt due to sloshing does not exceed 2000 times during a period when the number of vibrations is within that range.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: May 31, 2005
    Assignee: Siltronic AG
    Inventors: Yutaka Kishida, Teruyuki Tamaki, Seiki Takebayashi, Wataru Ohashi
  • Patent number: 6899758
    Abstract: The present invention provides a method and apparatus for growing a single crystal by the Czochralski method, wherein a single crystal is grown with forced cooling of neighborhood of a crystal growth interface by disposing a cooling cylinder formed of copper or a metal having a heat conductivity larger than that of copper at least in the vicinity of the crystal growth interface so as to surround the single crystal under pulling and circulating a cooling medium in the cooling cylinder. Thus, there are provided a method and apparatus for growing a single crystal, which can exert cooling effect on a growing single crystal to the maximum extent so as to realize higher crystal growth rate, even when a silicon single crystal having a diameter of 300 mm or more is grown.
    Type: Grant
    Filed: December 26, 2001
    Date of Patent: May 31, 2005
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Takao Abe, Toru Yamada
  • Patent number: 6896727
    Abstract: An improved method of determining the concentration of nitrogen within a wafer is provided. At least a portion of the nitrogen within the wafer is initially gettered to a gettering site. In order prevent the in-diffusion of nitrogen, a barrier layer is generally deposited upon the wafer prior to gettering the nitrogen within the wafer. The nitrogen is then measured at the gettering site. The concentration of nitrogen within the wafer is then determined based upon the measurement of nitrogen at the gettering site and the diffusion coefficient for nitrogen. In this regard, the diffusion coefficient of nitrogen permits the measurement of nitrogen at the gettering site to be translated into a measurement of the concentration of nitrogen throughout the entire wafer.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: May 24, 2005
    Assignee: SEH America, Inc.
    Inventor: Sergei V. Koveshnikov
  • Patent number: 6893499
    Abstract: According to the present invention, there is disclosed a silicon single crystal wafer grown according to the CZ method which is a wafer having a diameter of 200 mm or more produced from a single crystal grown at a growth rate of 0.5 mm/min or more without doping except for a dopant for controlling resistance, wherein neither an octahedral void defect due to vacancies nor a dislocation cluster due to interstitial silicons exists as a grown-in defect, and a method for producing it.
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: May 17, 2005
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Izumi Fusegawa, Koji Kitagawa, Ryoji Hoshi, Masahiro Sakurada, Tomohiko Ohta
  • Patent number: 6875269
    Abstract: Methods and apparatuses are useful to add polycrystalline rod material to the crucible of a CZ furnace and thereby increase utilization of crucible volume in the production of large diameter CZ silicon ingots. Multiple silicon rods are melted in the CZ furnace, and the subsequent production of a single crystal silicon ingot can occur without operating the isolation valve or opening the upper chamber of the furnace.
    Type: Grant
    Filed: November 13, 2002
    Date of Patent: April 5, 2005
    Assignee: Advanced Silicon Materials LLC
    Inventors: Torsten H. Hartmann, Henry Dare Wood
  • Patent number: 6869477
    Abstract: A process for preparing a single crystal silicon in accordance with the Czochralski method, is provided. More specifically, by quickly reducing the pull rate at least once during the growth of the neck portion of the single crystal ingot, in order to change the melt/solid interface shape from a concave to a convex shape, the present process enables zero dislocation growth to be achieved in a large diameter neck within a comparably short neck length, such that large diameter ingots of substantial weight can be produced safely and at a high throughput.
    Type: Grant
    Filed: February 20, 2001
    Date of Patent: March 22, 2005
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Hiroyo Haga, Makoto Kojima, Shigemi Saga
  • Patent number: 6866713
    Abstract: The present invention provides for a process for preparing a single crystal silicon ingot by the Czochralski method. The process comprises selecting a seed crystal for Czochralski growth wherein the seed crystal comprises vacancy dominated single crystal silicon.
    Type: Grant
    Filed: October 28, 2002
    Date of Patent: March 15, 2005
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Hariprasad Sreedharamurthy, Mohsen Banan
  • Patent number: 6860940
    Abstract: An automated macromolecular crystallization screening system wherein a multiplicity of reagent mixes are produced. A multiplicity of analysis plates is produced utilizing the reagent mixes combined with a sample. The analysis plates are incubated to promote growth of crystals. Images of the crystals are made. The images are analyzed with regard to suitability of the crystals for analysis by x-ray crystallography. A design of reagent mixes is produced based upon the expected suitability of the crystals for analysis by x-ray crystallography. A second multiplicity of mixes of the reagent components is produced utilizing the design and a second multiplicity of reagent mixes is used for a second round of automated macromolecular crystallization screening. In one embodiment the multiplicity of reagent mixes are produced by a random selection of reagent components.
    Type: Grant
    Filed: September 23, 2002
    Date of Patent: March 1, 2005
    Assignee: The Regents of the University of California
    Inventors: Brent W. Segelke, Bernhard Rupp, Heike I. Krupka
  • Patent number: 6858077
    Abstract: The present invention relates to a single crystalline silicon ingot, a single crystalline wafer, and a producing method thereof in accordance with the Czochralski method which enables reduction of a large defect area while increasing a micro-vacancy defect area in an agglomerated vacancy point area, which is the area between a central axis and an oxidation-induced stacking fault ring, by providing uniform conditions of crystal ingot growth and cooling and by adjusting a pulling rate for growing an ingot to grow, thus the oxidation-induced stacking fault ring exists only at an edge of the ingot radius.
    Type: Grant
    Filed: November 12, 2002
    Date of Patent: February 22, 2005
    Assignee: Siltron Inc.
    Inventors: Hong-Woo Lee, Joon-Young Choi, Hyon-Jong Cho, Hak-Do Yoo
  • Patent number: 6858076
    Abstract: There are provided a system for manufacturing a single-crystal ingot which is equipped with a cooler for cooling the single-crystal ingot being pulled and is capable of forming a tail without involvement of excessive heating of a crucible, as well as to a method for controlling the system. In a system for manufacturing a single-crystal ingot having a cooler for cooling a single-crystal ingot which is being pulled from molten raw material (called a single-crystal pulled ingot), when a tail of the single-crystal pulled ingot is formed, the cooler is moved away from the solid/melt interface between the single-crystal ingot and the molten raw material, to thereby reduce the power dissipated by the system. In the system, the cooler is moved upward after the end of a product area of the single-crystal ingot has been cooled until it passes through a grown-in defect temperature range.
    Type: Grant
    Filed: May 10, 2000
    Date of Patent: February 22, 2005
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Hirotaka Nakajima, Toshirou Kotooka, Yoshiyuki Shimanuki, Hiroshi Inagaki, Shigeki Kawashima, Makoto Kamogawa
  • Patent number: 6843847
    Abstract: A silicon single crystal wafer grown by the CZ method, which is doped with nitrogen and has an N-region for the entire plane and an interstitial oxygen concentration of 8 ppma or less, or which is doped with nitrogen and has an interstitial oxygen concentration of 8 ppma or less, and in which at least void type defects and dislocation clusters are eliminated from the entire plane, and a method for producing the same. Thus, there are provided a defect-free silicon single crystal wafer having an N-region for the entire plane, in which void type defects and dislocation clusters are eliminated, produced by the CZ method under readily controllable stable production conditions with a wide controllable range, and a method producing the same.
    Type: Grant
    Filed: November 7, 2000
    Date of Patent: January 18, 2005
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Makoto Iida, Masanori Kimura
  • Patent number: 6843848
    Abstract: A semiconductor wafer made from silicon which is doped with hydrogen. The hydrogen concentration is less than 5*1016 atcm?3 and greater than 1*1012 atcm?3. A method for producing a semiconductor wafer from silicon includes separating the semiconductor wafer from a silicon single crystal, with the single silicon crystal being pulled from a melt, in the presence of hydrogen, using the Czochralski method. The hydrogen partial pressure during the pulling of the single silicon crystal is less than 3 mbar.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: January 18, 2005
    Assignee: Siltronic AG
    Inventors: Wilfried Von Ammon, Rüdiger Schmolke, Erich Daub, Christoph Frey
  • Patent number: 6843849
    Abstract: In a method for growing a single crystal by bringing a seed crystal (4) into contact with a melt (2) of raw materials melted under heating in a crucible (1) a blade member (5) or a baffle member in disposed in the raw material melt (2) in the crucible (1) and a single crystal is grown by pulling up it with rotating the crucible (1) to thereby grow various single crystals including CLBO from the highly viscous raw material melt (2) as high quality and high performance crystals.
    Type: Grant
    Filed: May 22, 2000
    Date of Patent: January 18, 2005
    Assignee: Japan Science and Technology Corporation
    Inventors: Takatomo Sasaki, Yusuke Mori, Masashi Yoshimura
  • Publication number: 20040250749
    Abstract: The present invention provides methods and apparatuses for writing information to, reading information from, and erasing information on a luminescent data storage medium comprising Al2O3. The method includes writing and erasing of the information using photoionization via sequential two-photon absorption and non-destructive reading the information using fluorescent detection. The apparatuses for writing and reading the information incorporate confocal detection and spherical aberration correction for multilayer volumetric fluorescent data storage. The methods also allow multilevel recording and readout of information for increased storage capacity.
    Type: Application
    Filed: June 9, 2003
    Publication date: December 16, 2004
    Inventors: Mark S. Akselrod, Anna E. Akselrod
  • Patent number: 6830740
    Abstract: The present invention provides a method for producing a solar cell comprising forming the solar cell from a CZ silicon single crystal wafer, wherein a CZ silicon single crystal wafer having an initial interstitial oxygen concentration of 15 ppma or less is used as the CZ silicon single crystal wafer; a solar cell produced from a CZ silicon single crystal wafer, wherein the CZ silicon single crystal wafer has an interstitial oxygen concentration of 15 ppma or less; and a solar cell produced from a CZ silicon single crystal wafer, wherein the CZ silicon single crystal wafer has a BMD density of 5×108/cm3 or less. Thus, there can be obtained a solar cell showing little fluctuation of characteristics.
    Type: Grant
    Filed: February 11, 2003
    Date of Patent: December 14, 2004
    Assignees: Shin-Etsu Handotai Co., Ltd., Shin-Etsu Chemical Co., Ltd.
    Inventors: Konomu Oki, Takao Abe
  • Publication number: 20040244674
    Abstract: A method for growing a silicon single crystal used for semiconductor integrated circuit devices, wherein the single crystal is grown by the CZ method at a nitrogen concentration of 1×1013 atoms/cm3-1×1015 atoms/cm3 with a cooling rate of not less than 2.5° C./min at a crystal temperature of 1150° C.-1000° C., in which case, the pulling rate is adjusted such that the outside diameter of a circular region including oxidation-induced stacking faults generated at the center of a wafer which is subjected to the oxidation heat treatment at high temperature is not more than ⅗ of the wafer diameter, wherein the wafer is prepared by slicing the grown single crystal. In the growth method, the concentration of oxygen in the silicon single crystal is preferably not more than 9×1017 atoms/cm3 (ASTM '79).
    Type: Application
    Filed: June 6, 2003
    Publication date: December 9, 2004
    Inventors: Toshiaki Ono, Tadami Tanaka, Shigeru Umeno, Eiichi Asayama, Hideshi Nishikawa
  • Publication number: 20040237880
    Abstract: A method for manufacturing an optical member of a fluoride crystal includes: a growing step of growing an ingot of a fluoride crystal; a cutting-out step of cutting out from the ingot a cylindrical basic material with two parallel planes which have a certain crystal plane orientation; an orientation-determining step of determining a crystal orientation of a side surface of the cylindrical basic material; a birefringence-measuring step of measuring birefringence in a specific crystal axis direction at the side surface determined based on the crystal orientation determined in the orientation-determining step; and an evaluating step of evaluating the fluoride crystal on the basis of a result of measurement of the birefringence. A fluoride crystal is obtained in which a maximum value of birefringence in a specific crystal axis direction at a side surface is not more than 10 nm/cm at a measurement wavelength of 633 nm.
    Type: Application
    Filed: September 30, 2003
    Publication date: December 2, 2004
    Applicant: Nikon Corporation
    Inventors: Shigeru Sakuma, Kenichi Muramatsu, Kazuhiro Kido
  • Patent number: 6824608
    Abstract: A nucleant seed for epitaxial growth of single-crystal CaF2 includes SrF2. In some embodiments, YF3, LaF3, or rare-earth fluoride is substituted into the SrF2 structure.
    Type: Grant
    Filed: September 16, 2002
    Date of Patent: November 30, 2004
    Assignee: Corning Incorporated
    Inventors: George H. Beall, Charles W. Deneka, Gitimoy Kar
  • Publication number: 20040226504
    Abstract: In supplying crystalline materials in the Czochralski method, it is made use of an apparatus equipped with an inner vessel having an opening portion at the lower part or bottom thereof, which is to be charged with a granular solid material, an outer vessel containg the inner vessel therein with the function of sliding movement and thus closing the opening portion, and pull-up means for suspending the inner vessel and outer vessel in a manner causing them to ascend or descend, wherein the opening portion is opened through a sliding motion of the inner vessel or outer vessel for additional charging or recharging of the solid material into the molten material in the crucible, with the result that the molten material in the crucible can be prevented from splashing, the additional charging can be carried out in a static manner, the material cost becomes low and there is no risk of cracking due to rapid heating.
    Type: Application
    Filed: April 22, 2004
    Publication date: November 18, 2004
    Inventors: Katsunori Nakashima, Tatsuya Yabusame, Fumio Yamanaka
  • Patent number: 6814802
    Abstract: Methods and apparatus for concurrent growth of multiple crystalline ribbons from a single crucible employ meniscus shapers to facilitate continuous growth of discrete and substantially flat crystalline ribbons having controlled width.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: November 9, 2004
    Assignee: Evergreen Solar, Inc.
    Inventor: Richard Lee Wallace, Jr.
  • Patent number: 6811607
    Abstract: The present invention provides aluminum oxide crystalline materials including dopants and oxygen vacancy defects and methods of making such crystalline materials. The crystalline materials of the present invention have particular utility in optical data storage applications.
    Type: Grant
    Filed: December 4, 2002
    Date of Patent: November 2, 2004
    Assignee: Landauer, Inc.
    Inventor: Mark Akselrod
  • Publication number: 20040211354
    Abstract: A one-piece bowl of thermostructural composite material comprising fiber reinforcement densified by a matrix. The bowl is made by supplying deformable fiber in plies that are whole, being free from slots or cutouts, superposing said plies on a former of shape corresponding to the bowl to be made, deforming the plies, and bonding the superposed plies to one another by means of fibers extending transversely relative to the plies, e.g. by needling so as to obtain a bowl preform which is then densified. The bowl can be used as a support for a crucible in an installation for producing monocrystalline silicon.
    Type: Application
    Filed: May 24, 2004
    Publication date: October 28, 2004
    Inventors: Jean-Michel Guirman, Dominique Coupe, Jean-Michel Georges
  • Patent number: 6805742
    Abstract: A semiconductor substrate after heat-treatment in a non-oxidising atmosphere has the characteristics that the depth of the denuded zone may be greater than 12 &mgr;m or the defect-free depth of the void type defect is greater than 12 &mgr;m and the substrate has a locally densified portion produced by nitrogen segregation and exhibiting a signal strength two or more times the average signal strength at the depth of 12 &mgr;m or more below the surface thereof when measuring the concentration of nitrogen by using secondary ion mass-spectroscopy, and the density of the crystal defect of oxygen precipitates is 5×108/cm3 or more, and the said substrate is produced by heat-treating for at least one hour at the temperature of 1200° C. or more in a non-oxidising atmosphere.
    Type: Grant
    Filed: August 7, 2002
    Date of Patent: October 19, 2004
    Assignee: Siltronic AG
    Inventors: Akiyoshi Tachikawa, Kazunori Ishisaka, Atsushi Ikari
  • Patent number: 6803331
    Abstract: A process for the heat treatment of a silicon wafer, during which the silicon wafer is at least temporarily exposed to an oxygen-containing atmosphere, the heat treatment taking place at a temperature which is selected in such a way that the inequality [ Oi ] < [ Oi ] eq ⁢ ( T ) ⁢ exp ⁢ ( 2 ⁢ σ SiO 2 ⁢ Ω rkT ) is satisfied, where [Oi] is the oxygen concentration in the silicon wafer [Oi]eq(T) is the limit solubility of oxygen in silicon at a temperature T, &sgr;SiO2 is the surface energy of silicon dioxide &OHgr; is the volum
    Type: Grant
    Filed: February 4, 2003
    Date of Patent: October 12, 2004
    Assignee: Siltronic AG
    Inventors: Robert Hölzl, Christoph Seuring, Reinhold Wahlich, Wilfried Von Ammon
  • Patent number: 6802899
    Abstract: There is provided a manufacturing process for a CZ silicon single crystal wafer which is subjected to heat treatment wherein slip resistance of a portion of the CZ silicon single crystal wafer in contact with a heat treatment boat is improved with extreme simplicity, convenience and very low cost. A silicon single crystal rod is grown by means of a Czochralski method in a condition that an OSF ring region is formed in a peripheral region of the silicon single crystal rod and the grown silicon signal crystal rod is processed into silicon single crystal wafers, whereby the silicon single crystal wafer is obtained such that when the silicon single crystal wafer is subjected to heat treatment, at least a portion of the silicon single crystal wafer in contact between the wafer and the boat is formed of an OSF ring region.
    Type: Grant
    Filed: July 9, 2001
    Date of Patent: October 12, 2004
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventor: Masaro Tamatsuka
  • Patent number: 6800132
    Abstract: A method for producing a silicon ingot through pulling up a silicon single crystal according to the Czochralski method, wherein the silicon single crystal is pulled up while being doped with nitrogen in such a condition as to form a part having a nitrogen content of 5×1013 atoms/cm3 to 1×1015 atoms/cm3. A silicon wafer having a nitrogen content of 5×1013 atoms/cm3 to 1×1015 atoms/cm3 which is suitable for being treated with heat in a non-oxidizing atmosphere is manufactured of an ingot produced by using the method. The method can be used for producing a silicon wafer being doped with nitrogen and having satisfactory characteristics for use in a semiconductor device.
    Type: Grant
    Filed: February 12, 2002
    Date of Patent: October 5, 2004
    Assignee: Komatsu Denshi Sinzoku Kabushiki
    Inventors: Satoshi Komiya, Shiro Yoshino, Masayoshi Danbata, Kouichirou Hayashida
  • Publication number: 20040187767
    Abstract: A method for making ingots, and devices for making ingots are provided. Crucibles are provided that are reusable for forming multicrystalline silicon ingots. Crucibles are provided with features such as multiple components, coefficients of thermal expansion, and coatings that enhance a release of the ingots from the crucibles after cooling. Coatings on crucibles are provided that reduce or eliminate contamination of silicon ingots during formation. Methods of forming composite wafers are provided that produce a low cost wafer without sacrificing performance.
    Type: Application
    Filed: October 24, 2003
    Publication date: September 30, 2004
    Applicant: Intel Corporation
    Inventors: Mohan Chandra, Bernard D. Jones, P. Santhana Raghavan, Carl Chartier, Alleppey V. Hariharan, Tom McGee, Dean C. Skelton
  • Patent number: 6797061
    Abstract: Provided are a quartz glass crucible for pulling up a silicon single crystal, with which not only a defectless silicon single crystal can be pulled but a single crystallization ratio can greatly be improved and a production method therefor. The quartz glass crucible comprises a crucible body constituted of a semi-transparent quartz glass layer and a transparent quartz glass layer formed on the inner wall surface of the crucible bass body and no expanded bubbles equal to ro more than 0.5 mm in diameter are present in a layer 1 mm in depth from an inner surface of the quartz glass crucible after the silicon single crystal is pulled up using the quartz glass crucible.
    Type: Grant
    Filed: November 14, 2001
    Date of Patent: September 28, 2004
    Assignee: Shin Etsu Quartz Products Co., Ltd.
    Inventors: Tatsuhiro Sato, Shigeo Mizuno, Yasuo Ohama
  • Patent number: RE39173
    Abstract: A method of making silicon single crystal wafers free of grown-in defects is provided. These wafers are formed from silicon single crystal manufactured by the Czochralski method. Careful control of the pulling rate, V (mm/min), and the temperature gradient G (° C./mm) permits crystals to be formed that are free from OSF rings, and other types of defects.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: July 11, 2006
    Assignee: Sumitomo Mitsubishi Silicon Corporation
    Inventors: Masataka Hourai, Eiji Kajita