With Means For Measuring, Testing, Or Sensing Patents (Class 117/201)
  • Patent number: 6375739
    Abstract: Apparatus for bulk vapor phase crystal growth comprising: at least one source zone and at least one sink zone each associated with means for independent temperature control within the zone; and at least one passage means adapted for transport of vapor from source to sink zone; and additionally comprising means for in-situ monitoring of the sink zone; wherein means for monitoring is substantially non-intrusive in terms of temperature regulation within the sink zone; process for bulk vapor phase crystal growth employing the apparatus; method for starting up the process; method for controlling the process; use for any bulk vapor transport technique; equipment for monitoring growth using the apparatus or process; and crystal grown with the apparatus or process.
    Type: Grant
    Filed: February 18, 2000
    Date of Patent: April 23, 2002
    Assignee: University of Durham
    Inventor: John Tomlinson Mullins
  • Patent number: 6368405
    Abstract: A single crystal silicon growth apparatus, comprising: a chamber where a silicon substrate is to be inserted; a heat source for rising the temperature in an interior of the chamber; a cooling line for rapidly dropping the temperature in the interior of the chamber; a gas sprayer for providing a source gas and a purge gas inside the chamber; a gas inflow line connected to the gas sprayer for inflowing the source gas and the purge gas into the gas sprayer; and a gas exhausting line for maintaining the interior of the chamber with a vacuum.
    Type: Grant
    Filed: December 13, 1999
    Date of Patent: April 9, 2002
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventor: Seung Woo Shin
  • Publication number: 20020038627
    Abstract: A low dislocation density silicon carbide (SiC) is provided as well as an apparatus and method for growing the same. The SiC crystal, grown using sublimation techniques, is preferably divided into two stages of growth. During the first stage of growth, the crystal grows in a normal direction while simultaneously expanding laterally. Although dislocations and other material defects may propagate within the axially grown material, defect propagation and generation in the laterally grown material are substantially reduced, if not altogether eliminated. After the crystal has expanded to the desired diameter, the second stage of growth begins in which lateral growth is suppressed and normal growth is enhanced. A substantially reduced defect density is maintained within the axially grown material that is based on the laterally grown first stage material.
    Type: Application
    Filed: February 14, 2001
    Publication date: April 4, 2002
    Inventors: Yury Alexandrovich Vodakov, Mark Grigorievich Ramm, Evgeny Nikolaevich Mokhov, Alexandr Dmitrievich Roenkov, Yury Nikolaevich Makarov, Sergei Yurievich Karpov, Mark Spiridovich Ramm, Heikki I. Helava
  • Patent number: 6349271
    Abstract: In a process simulating method for simulating an oxidation process of a semiconductor device manufacturing step, even when the respective elements of this semiconductor device own arbitrary shapes, a time step of an oxidizing agent diffusion within an oxide film can be properly calculated in the oxidation process.
    Type: Grant
    Filed: July 20, 1998
    Date of Patent: February 19, 2002
    Assignee: NEC Corporation
    Inventor: Yutaka Akiyama
  • Patent number: 6344084
    Abstract: A combinatorial molecular layer epitaxy apparatus is provided which includes a common chamber (22) having pressure therein controllable; one or more conveyable substrate heating units (36) having a substrate holder (48) for holding one or more substrates in the common chamber; and one or more process conducting chambers (24, 26, 28) having pressure therein controllable and provided to correspond to the substrate heating units.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: February 5, 2002
    Assignee: Japan Science and Technology Corporation
    Inventors: Hideomi Koinuma, Masashi Kawasaki
  • Publication number: 20010055689
    Abstract: A silicon wafer is provided having controlled distribution of defects, in which denuded zones having a sufficient depth inward from the surface of the wafer are combined with a high gettering effect in a bulk region of the wafer. In the silicon wafer, oxygen precipitates, which act as intrinsic gettering sites, show vertical distribution. The oxygen precipitate concentration profile from the top to the bottom surfaces of the wafer includes first and second peaks at first and second predetermined depths from the top and bottom surfaces of the wafer, denuded zones between the top and bottom surfaces of the wafer and each of the first and second peaks, and a concave region between the first and second peaks, which corresponds to a bulk region of the wafer. For such an oxygen precipitate concentration profile, the wafer is exposed to a rapid thermal annealing process in a gas mixture atmosphere comprising ammonia (NH3) and argon (Ar) at temperatures below about 1200° C.
    Type: Application
    Filed: June 28, 2001
    Publication date: December 27, 2001
    Inventor: Jea-gun Park
  • Patent number: 6325851
    Abstract: SLH, CLH, and an output of the weight sensor enter a main control section to calculate MD, MDD, and WEL. The main control section makes up a negative-loop for stable automatic control. This section calculates GR(GL), SLC(GWD), SLC(MP), and SLC(WEL) for SL and CL control, and calculates crucible moving rate from GD(GL) and CI(MD), and determines SL and CL by using these parameters to control crystal-growing.
    Type: Grant
    Filed: September 13, 1999
    Date of Patent: December 4, 2001
    Assignee: Komatsu Electronic Metals Co.
    Inventor: Shuji Onoue
  • Publication number: 20010018891
    Abstract: A scale in the nanometer range for technical devices which are used for the high-resolution or ultrahigh-resolution imaging of structures. To construct the scale, at least two different crystalline or amorphous materials are used, which, when imaged, are easily distinguished from one another by their contrast. These material layers are deposited using a suitable material deposition method as a heterolayer sequence onto a substrate material. The produced heterolayer sequence is characterized experimentally using an analysis method that is sensitive to the individual layer thicknesses of the heterolayer sequence. The data obtained from the analysis method are evaluated and recorded. The layer structure is exposed by splitting open the heterolayer sequence in the deposition direction. The scale is suited for calibrating technical devices used for scanning electron microscopy, scanning transmission electron microscopy, or scanning probe microscopy (atomic force microscopy, scanning tunneling microscopy).
    Type: Application
    Filed: December 28, 2000
    Publication date: September 6, 2001
    Applicant: Deutsche Telekom AG
    Inventors: Rainer Loesch, Hartmut Hillmer, Winfried Schlapp, Armin Poecker, Walter Betz, Rainer Goebel
  • Patent number: 6284039
    Abstract: The present invention is directed to a set of epitaxial silicon wafers assembled in a wafer cassette, boat or other wafer carrier. Each wafer comprises a single crystal silicon substrate having an axially symmetric region in which silicon self-interstitials are the predominant intrinsic point defect and which is substantially free of agglomerated defects, and an epitaxial layer which is deposited upon a surface of the substrate and which is substantially free of grown-in defects caused by the presence of agglomerated silicon self-interstitial defects on the substrate surface upon which the epitaxial layer is deposited.
    Type: Grant
    Filed: October 13, 1999
    Date of Patent: September 4, 2001
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Luciano Mule'Stagno, Lu Fei, Joseph C. Holzer, Harold W. Korb, Robert J. Falster
  • Publication number: 20010008117
    Abstract: Heat shields for Czochralski pullers include a ring-shaped heat shield housing comprising inner and outer heat shield housing walls and an oblique heat shield housing floor and a heat shield housing roof that extend between the inner and outer heat shield housing walls. The heat shield housing contains insulating material therein. A support member is configured to support the heat shield housing within the crucible in a Czochralski puller. In one embodiment, the support member includes at least one support arm that extends to the ring-shaped heat shield housing. The at least one support arm may be hollow and may contain insulating material therein. In another embodiment, the support member is a ring-shaped support member. The ring-shaped support member may include inner and outer support member walls containing insulating material therebetween. The ring-shaped support member may also include at least one window therein. The ring-shaped member may be oblique.
    Type: Application
    Filed: March 9, 2001
    Publication date: July 19, 2001
    Inventor: Jae-gun Park
  • Patent number: 6241818
    Abstract: A method and system for controlling growth of a taper portion of a semiconductor single crystal based on the slope of the taper. A crystal drive unit pulls the growing crystal from a melt at a target pull rate that substantially follows an initial velocity profile for growing the taper. A controller calculates a taper slope measurement as a function of a change in crystal diameter relative to a change in crystal length. The controller then generates an error signal as a function of the difference between the taper slope measurement and a target taper slope and provides a pull rate correction to the crystal drive unit as a function of the error signal. In turn, the crystal drive unit adjusts the pull rate according to the pull rate correction to reduce the difference between the taper slope measurement and the target taper slope. The target taper slope is defined by a function having a generally exponential component and a generally linear component.
    Type: Grant
    Filed: April 7, 1999
    Date of Patent: June 5, 2001
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Steven L. Kimbel, Robert R. Wyand, III
  • Patent number: 6203611
    Abstract: A control method for use with a Czochralski crystal puller. The method includes pulling the growing crystal from the melt at a first target pull rate to grow a taper portion of the crystal and measuring the crystal diameter of the taper. The method also includes estimating a slope of the diameter as a function of a change in crystal diameter relative to time and the first target pull rate. The method further includes predicting a crystal diameter Di at which to initiate body growth from the taper as a function of the estimated slope. By increasing the pull rate to a second target pull rate when the measured crystal diameter reaches the predicted crystal diameter Di, the method controls growth of the crystal for transitioning from taper growth to body growth. The method also determines the second target pull rate as a function of the estimated slope when using a predefined diameter Di at which to initiate growth of the crystal body.
    Type: Grant
    Filed: October 19, 1999
    Date of Patent: March 20, 2001
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Steven L. Kimbel, Robert R. Wyand, III
  • Patent number: 6203610
    Abstract: A device for monitoring a melt for the production of crystals. A camera is provided which images at least portions of the surface of the contents of a crucible. An evaluating device is used to evaluate the camera's images with respect to solid and liquid portions of the surface of the crucible contents.
    Type: Grant
    Filed: May 17, 1999
    Date of Patent: March 20, 2001
    Assignee: Leybold Systems GmbH
    Inventors: Burkhard Altekrüger, Joachim Aufreiter, Dieter Brüss, Klaus Kalkowski
  • Patent number: 6200383
    Abstract: The invention features a method of controlling the depth of a melt for or crystal growth. According to the method, an input signal is applied through a crucible and a material disposed within the crucible. An output signal generated in response to the input signal is measured. The output signal relates to the depth of the melt. An amount of the source material introduced into the melt is adjusted to maintain the depth of the melt at a substantially constant level using the output signal.
    Type: Grant
    Filed: May 3, 1999
    Date of Patent: March 13, 2001
    Assignee: Evergreen Solar, Inc.
    Inventors: Richard L. Wallace, Jr., Richard C. Krauchune
  • Patent number: 6175644
    Abstract: Provided is the ability to validate detected features in acquired images to thereby enhance the integrity of any analysis carried out on the detected and validated features. A sequence of images of, e.g., an object is acquired, each image in the sequence corresponding to a distinct orientation of the object about a selected object axis. Images in the sequence are inspected for feature points of the selected feature plane, as-projected into the images, at a first feature detection location and at a second feature detection location. The second feature detection location is configured at an image position at which a feature point detected in the first feature detection location in a first inspected image is expected to appear in a second inspected image. Valid object feature points are identified as being those feature points which are detected in both the first feature detection location in a first inspected image and in the second feature detection location in a second inspected image of the image sequence.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: January 16, 2001
    Assignee: Cognex Corporation
    Inventors: Joseph R. Scola, Vladimir N. Ruzhitsky, Lowell D. Jacobson
  • Patent number: 6171391
    Abstract: A method and system for determining melt level and reflector position in a Czochralski single crystal growing apparatus. The crystal growing apparatus has a heated crucible containing a silicon melt from which the crystal is pulled. The crystal growing apparatus also has a reflector positioned within the crucible with a central opening through which the crystal is pulled. A camera generates images of a portion of the reflector and a portion of a reflection of the reflector visible on the top surface of the melt. An image processor processes the images as a function of their pixel values to detect an edge of the reflector and an edge of the reflection in the images. A control circuit determines a distance from the camera to the reflector and a distance from the camera to the reflection based on the relative positions of the detected edges in the images.
    Type: Grant
    Filed: October 14, 1998
    Date of Patent: January 9, 2001
    Assignee: Memc Electronic Materials, Inc.
    Inventors: Robert H. Fuerhoff, Mohsen Banan
  • Patent number: 6159284
    Abstract: A process and a device will produce a cylindrical single crystal of semicuctor material with the smallest possible alignment error of the crystal lattice. A process for cutting semiconductor wafers from two or more such single crystals is by means of wire sawing. The process for producing the single crystal is as follows: (a) a single crystal with an alignment error of the crystal lattice equal to at most 1.5.degree.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: December 12, 2000
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien AG
    Inventors: Hans Olkrug, Holger Lundt, Christian Andrae, Josef Frumm
  • Patent number: 6126745
    Abstract: A device for controlling crystal growth processes which run through various process phases, for instance, melting or cool-down, and in which the shape of the crystal has different areas during growth, for instance, a neck and/or a shoulder. Certain process parameters and target values, as well as input values and output values, for instance, a certain gas pressure or a certain rotational speed, are also associated with each of these areas and phases. The linking of these parameters is accomplished by function generators or tables. With the aid of the control device, it is made possible to generate a specially adapted linking of the respectively necessary input and output parameters for each of the special process phases and crystal sections with an essentially uniform construction and a comprehensible structure.
    Type: Grant
    Filed: February 19, 1999
    Date of Patent: October 3, 2000
    Assignee: Leybold Systems GmbH
    Inventors: Burkhard Altekruger, Joachim Aufreiter, Dieter Bruss, Klaus Kalkowski
  • Patent number: 6120601
    Abstract: An apparatus and method for precisely calibrating the transfer arm of a multiple station wafer processing system without breaking vacuum and with a minimum of system downtime is provided. A system of determining and properly aligning the crystallographic orientation of the wafers before processing as well as monitoring the orientation of individual wafers during wafer transfer between processing stations is also provided.
    Type: Grant
    Filed: October 10, 1996
    Date of Patent: September 19, 2000
    Assignee: Varian Semiconductor Equipment Associates, Inc.
    Inventors: Richard F. Landau, Edward D. Schultheis
  • Patent number: 6106612
    Abstract: A level detector detects the level of an approximately flat surface of a substance in a container. The level detector illuminates a portion of the surface, and detects the location of the illuminated portion on the surface. Based on detecting the location of the illuminated portion, the level detector generates a signal related to the level of the surface, which can represent the level of the surface in a direction perpendicular to the surface. A method for determining a level of a surface of a substance in a container includes illuminating a portion of the surface, detecting a location of the illuminated portion on the surface, and generating a signal related to the level of the surface based on the result of detecting the location of the illuminated portion.
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: August 22, 2000
    Assignee: SEH America Inc.
    Inventor: Barton V. White
  • Patent number: 6099642
    Abstract: An object of the invention is to provide a single crystal clamping device and a single crystal supporting method. The single crystal clamping device does not become inclined and does not vibrate, and the center of the single crystal clamping device is congruous to the center of the growing single crystal.
    Type: Grant
    Filed: June 2, 1998
    Date of Patent: August 8, 2000
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Shoei Kurosaka, Hiroshi Inagaki, Shigeki Kawashima, Junsuke Tomioka
  • Patent number: 6093244
    Abstract: A method and system for controlling the thickness of a pair of dendrites in a dendritic silicon web growth process to improve dendritic silicon web production. An image of each dendrite in a web emerging from a silicon melt in a furnace is produced by a pair of cameras focused on the dendrite pair. The dendrite images are digitized, the average thickness of the dendrites is calculated, and compared to set point parameters. The average difference between the dendrite thicknesses and the set point parameters is used to control the overall furnace temperature, while the differences between the thickness of each pair are used to control the lateral temperature distribution in the furnace in order to maintain the dendrite thickness within predetermined limits.
    Type: Grant
    Filed: April 10, 1997
    Date of Patent: July 25, 2000
    Assignee: Ebara Solar, Inc.
    Inventors: John R. Easoz, Barry Munshower
  • Patent number: 6074485
    Abstract: A STM drive mechanism capable of moving a scanning tunneling microscope (STM) incorporated with a molecular beam epitaxy (MBE) device in the MBE device under vacuum and a substrate holder with a wide clearance formed between a substrate heating system and the substrate holder are provided. The STM is protected by a heat insulating shield from high vapor pressure atmosphere and radiant heat according to substrate heating.
    Type: Grant
    Filed: December 8, 1998
    Date of Patent: June 13, 2000
    Assignee: National Research Institute for Metals
    Inventors: Shiro Tsukamoto, Nobuyuki Koguchi
  • Patent number: 6071341
    Abstract: An apparatus for fabricating single-crystal silicon easily controlling a temperature gradient based on the Czochralski (CZ) method, and more particularly preventing as-grown defects created in order to obtain high-quality single-crystal silicon.The above-mentioned apparatus includes a first thermal shield member surrounding the pulling single-crystal silicon and a second thermal shield member inside the first thermal shield member, surrounding the pulling single-crystal silicon. The second thermal shield member is fixed on the first thermal shield member by a support located on the external surface of the second thermal shield member and connected to the first thermal shield member. The surroundings of a solid-liquid interface are extremely cooled by using the first thermal shield member, thereby a stable shape of the single-crystal silicon is formed. The temperature gradient of the temperature region of 1000.degree. C..about.1200.degree. C.
    Type: Grant
    Filed: May 21, 1997
    Date of Patent: June 6, 2000
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Yoshiyuki Shimanuki, Toshimichi Kubota, Toshirou Kotooka, Makoto Kamogawa
  • Patent number: 6071340
    Abstract: A method of and system for determining the melt-level in a crystal growing system. A rangefinder emits a signal to reflect off the melt. The reflected signal is directed to a retroreflector. The retroreflector redirects the signal along a parallel path back to the melt surface. The redirected signal is reflected off the melt surface back to the rangefinder, where it is analyzed to determine the distance traveled by the signal. From this, changes in melt-level are determined and the melt-level may be appropriately controlled.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: June 6, 2000
    Assignee: General Signal Technology Corporation
    Inventor: Zhixin Li
  • Patent number: 6068699
    Abstract: The present invention utilizes a weighing detector as well as a weighing diameter-controlling method in a crystal-pulling apparatus using a wire method for measuring the crystal weight in accuracy. A pulling wire 4 and a wire rolling means 20, having a wire rolling drum 21, suspended on a weighing detector 2 in a freely rotating way. Accordingly, in the weighing detector 2, the weights of the pulling wire 4 and the wire rolling means 20 are served to balance the loading weight. In addition, the vertical central line 6 of the weighing detector, the rotating axis of the wire rolling drum 21, the rotating axis of the wire rolling means 20, and the axis of pulling crystals are all consistent. Consequently, the whole gravity center is located on the vertical central line of the weighing detector 2. When pulling the single crystals at the same time as rolling the wire, the gravity center of the wire rolling means is shifted merely depending on the diameter variation at the pulling wire.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: May 30, 2000
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Hideki Tsuji, Mitsunori Kawabata, Yoshinobu Hiraishi
  • Patent number: 6066205
    Abstract: Large diameter single crystals of aluminum nitride (AlN) are grown isotropically by injecting a nitrogen-containing gas into liquid aluminum at elevated temperatures. A seed crystal that is maintained at a temperature below that of the surrounding liquid aluminum is pulled from the melt, while the AlN that is formed in the melt is deposited on the seed crystal. An apparatus for carrying out the method is also disclosed.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: May 23, 2000
    Assignee: Cree, Inc.
    Inventor: Charles Eric Hunter
  • Patent number: 6056819
    Abstract: In the pulling of a single crystal, hitherto, it is difficult to reduce the OSF density while the deformation rate is held down within the tolerance, so that it is difficult to improve the quality and productivity. In the present invention, a deviation from a true circle in each part of a single crystal S.sub.n-1 which was pulled in the preceding batch is found and the pulling speed pattern f.sub.pn-1 (L.sub.1) in the preceding batch is updated (f.sub.pn (L.sub.1)) before a single crystal S.sub.n is pulled, in order to pull the single crystal as fast as possible so that the OSF density is small while the deviation is within the tolerance.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: May 2, 2000
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Masahiro Ogawa, Toshiyuki Yamamoto, Yoshiyuki Kashiwara, Tokuji Maeda
  • Patent number: 6053974
    Abstract: A heat shield for use in a crystal puller around a monocrystalline ingot grown out of a crucible in the crystal puller filled with molten semiconductor source material. The heat shield includes a reflector having a central opening sized and shaped for surrounding the ingot as the ingot is grown to reduce heat transfer from the crucible. The reflector is adapted to be supported in the crystal puller between the molten material and a camera aimed toward at three separate points on a meniscus formed between the ingot and an upper surface of the molten material. The reflector has at least three passages extending through the reflector. Each of the passages is located along an imaginary line extending between the camera and one of the points on the meniscus. This permits the camera to view the points so the positions of the points can be determined by the camera for calculating the diameter of the ingot while minimizing heat loss through the passages.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: April 25, 2000
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: William L. Luter, Lee W. Ferry
  • Patent number: 6051064
    Abstract: An apparatus for weighing single crystals during Czochralski crystal growing processes includes a pivotal elongated member such as a beam, a contact element and a load sensor. The load sensor can be mounted to at least one of the elongated member and a support surface of a crystal growing vessel. The beam is attached to a lift for pulling single crystals from a melt. During crystal growing, the weight of the grown crystal causes increased loading along the elongated member such that the contact element exerts an increasing force on the load sensor. The contact element and load sensor have respective contact surfaces which are shaped such that the force exerted on the load sensor corresponds substantially to the weight of grown single crystal. Typically, at least one of the contact surfaces is a rolling surface.
    Type: Grant
    Filed: August 20, 1998
    Date of Patent: April 18, 2000
    Assignee: SEH America, Inc.
    Inventor: Aaron L. Labrie
  • Patent number: 6045610
    Abstract: A silicon ingot is manufactured in a hot zone furnace by pulling the ingot from a silicon melt in the hot zone furnace in an axial direction, at a pull rate profile of the ingot from the silicon melt in the hot zone furnace that is sufficiently high so as to prevent interstitial agglomerates but is sufficiently low so as to confine vacancy agglomerates to a vacancy rich region at the axis of the ingot. The ingot so pulled is sliced into a plurality of semi-pure wafers each having a vacancy rich region at the center thereof that includes vacancy agglomerates and a pure region between the vacancy rich region and the wafer edge that is free of vacancy agglomerates and interstitial agglomerates.
    Type: Grant
    Filed: December 12, 1997
    Date of Patent: April 4, 2000
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jea-gun Park, Kyoo-chul Cho, Gon-sub Lee
  • Patent number: 6042646
    Abstract: A single crystal is pulled to a length at which the beginning of the body of the single crystal is assumed sufficiently to have been cooled down to a temperature below 1000.degree. C.; then the single crystal being pulled is detached from the molten silicon by pulling it at a speed high enough to cut it out from the molten silicon. Then oxygen precipitation heat-treatment is performed on the single crystal to locate the portion of AOP. AOP arises at the boundary of grown-in defects being formed zone while the single crystal passes through 1100.degree. C., and the position is at about 1100.degree. C. immediately before, detaching the single crystal out from the molten silicon. Therefore, the position at temperature 1100.degree. C. in the single crystal immediately before detaching the single crystal out from the molten silicon are known, then the temperature distributions of the single crystal immediately before detaching it out from the molten silicon can be decided easily.
    Type: Grant
    Filed: January 29, 1998
    Date of Patent: March 28, 2000
    Assignee: Komatsu Electric Metals Co., Ltd.
    Inventors: Fumitaka Ishikawa, Toshiaki Saishoji, Kozo Nakamura
  • Patent number: 6036775
    Abstract: A process is disclosed for continuously producing a single crystal by drawing downwardly a melt of a single crystal raw material, wherein a single crystal body grown from the melt is continuously pulled downwardly, and a plurality of single crystal products are continuously formed by intermittently cutting the single crystal body being downwardly moved.
    Type: Grant
    Filed: July 21, 1999
    Date of Patent: March 14, 2000
    Assignee: NGK Insulators, Ltd.
    Inventors: Minoru Imaeda, Akihiko Honda, Katsuhiro Imai, Yuichiro Imanishi, Nobuyuki Kokune, Shoji Sogo, Kazuaki Yamaguchi, Tetsuo Taniuchi
  • Patent number: 6030451
    Abstract: A method and apparatus for measuring and controlling the diameter of a silicon single crystal ingot grown by the Czochralski technique using dual optical cameras focused on diametrically opposed edges of the meniscus of the growing crystal to measure the actual crystal diameter. The crystal growth parameters can be adjusted in response to the measured diameter to maintain a constant, desired diameter. The method and apparatus of the invention provide a continuous accurate measurement of the crystal diameter and avoid unnecessary adjustments to the crystal growth conditions resulting from diameter measurement errors due to the effects of crystal orbit, melt level changes and camera angle variations.
    Type: Grant
    Filed: January 12, 1998
    Date of Patent: February 29, 2000
    Assignee: SEH America, Inc.
    Inventors: Aaron LaBrie, Masahiko Baba
  • Patent number: 6019841
    Abstract: The invention is an improved method and apparatus for growing crystals that incorporates an isolation valve between the growth and injection chambers to allow the growth chamber to be maintained at operating temperature and pressure while decoupling the injector chamber in order to make changes necessary to restart or advance the process. Separate heating elements in the injector assembly or chamber provide related heating control. Upper and lower load cells and programmable signal amplifiers are configured to weigh and output the dynamic weight range of the loss or gain of process materials of the growth chamber crucible and the injector assembly, and are connected by electrical slip rings or wireless means to a computer control system.
    Type: Grant
    Filed: March 24, 1998
    Date of Patent: February 1, 2000
    Assignee: G.T. Equuipment Technologies Inc.
    Inventors: Ijaz H. Jafri, Mohan Chandra, Rick C. White, Kedar P. Gupta, Robert B. Farmer, Bernard D. Jones, David F. Bliss
  • Patent number: 6010568
    Abstract: An apparatus and a method capable of automatically adjusting an initial position of the surface of a melt without an operator are provided. In a single crystal puller using a wire as a suspender for a seed crystal for growing a single crystal of silicon or the like according to the CZ method, a reference position of the seed crystal is detected, the wire is unwound to lower the end of the wire to a position higher by a distance W-X from the reference position and then pulled upward above said reference position to correct the wire for an extension due to the weight of a single crystal attached thereto. Also, the wire is left above a melt for about ten minutes to provide a constant amount of extension to the wire due to heat of the melt. These operations are automatically performed.
    Type: Grant
    Filed: January 7, 1999
    Date of Patent: January 4, 2000
    Assignee: Shin-Estu Handotai Co., Ltd.
    Inventors: Masahiko Urano, Atsushi Ozaki, Tomohiro Kakegawa, Hideki Nakano
  • Patent number: 6004393
    Abstract: 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: Grant
    Filed: January 22, 1999
    Date of Patent: December 21, 1999
    Assignees: 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
  • Patent number: 6001175
    Abstract: A method and apparatus of producing a crystal by using of vapor growth process, wherein: a high-frequency coil or conductor having a coil or conductor surface to generate a plane-like induction electric field is arranged so that at least one gas blowout port is connected to the coil or conductor surface so as to face a solid substrate; and a component element or a chemical compound is continuously precipitated and grown on a surface of the solid substrate at a temperature of not higher than the melting point of the solid substrate while the solid substrate is inductively heated by the high-frequency coil or conductor and a raw gas is supplied onto the surface of the solid substrate through the gas blowout port, to thereby produce a polycrystal or monocrystal thin film.
    Type: Grant
    Filed: March 4, 1996
    Date of Patent: December 14, 1999
    Inventors: Mitsuhiro Maruyama, Yasuhiro Maruyama
  • Patent number: 5997635
    Abstract: An apparatus and a method for fabricating a single-crystal semiconductor by means of CZ method are provided for improving the quality control through the modification of thermal cycle of a pulled single-crystal semiconductor. The apparatus includes a ring after heater which is capable of elevation. The method decreases a temperature gradient to smaller than 20.degree. C./cm, and preferably under 15.degree. C./cm, when the pulled single-crystal semiconductor is cooled from 1200.degree. C. to 1000.degree. C. The after heater therefore heats the single-crystal semiconductor where there is a temperature of 100-300.degree. C. lower than the range of 1200-1000.degree. C. A thermal shelter is provided to retain a temperature gradient of larger than 20.degree. C./cm when the single-crystal semiconductor is within the temperature range between the melting point and 1250.degree. C. The after heater and the shelter can be raised to an upper portion when polysilicon blocks are charged and a twisting step is carried out.
    Type: Grant
    Filed: January 22, 1998
    Date of Patent: December 7, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Toshimichi Kubota, Toshiro Kotooka, Makoto Kamogawa
  • Patent number: 5961934
    Abstract: A method and apparatus for dynamically controlling the crystallization of proteins including a crystallization chamber or chambers for holding a protein in a salt solution, one or more salt solution chambers, two communication passages respectively coupling the crystallization chamber with each of the salt solution chambers, and transfer mechanisms configured to respectively transfer salt solution between each of the salt solution chambers and the crystallization chamber. The transfer mechanisms are interlocked to maintain the volume of salt solution in the crystallization chamber substantially constant. Salt solution of different concentrations is transferred into and out of the crystallization chamber to adjust the salt concentration in the crystallization chamber to achieve precise control of the crystallization process.
    Type: Grant
    Filed: February 18, 1998
    Date of Patent: October 5, 1999
    Assignee: Biospace International Inc.
    Inventors: Leonard Arnowitz, Emanuel Steinberg
  • Patent number: 5961716
    Abstract: A CCD camera is used to measure the diameter of a growing crystal through optical recognition of the luminous ring at a crystal-melt interface. The result is an optical diameter control method and apparatus that eliminates the negative effects of orbit, melt-level and incorrect camera angle. The CCD camera is positioned such that it focuses on a full half of the circumference of the crystal as it is being grown. An automatic control system uses two points diametrically opposed on the crystal to measure the diameter, and a third point on the crystal closest to the camera to compute the melt level error. The automatic control system controls a crucible height and a crystal pull rate to optimize crystal diameter.
    Type: Grant
    Filed: December 15, 1997
    Date of Patent: October 5, 1999
    Assignee: SEH America, Inc.
    Inventors: Barton V. White, David J. Vickrey
  • Patent number: 5961720
    Abstract: A process is disclosed for continuously producing a single crystal by drawing downwardly a melt of a single crystal raw material, wherein a single crystal body grown from the melt is continuously pulled downwardly, and a plurality of single crystal products are continuously formed by intermittently cutting the single crystal body being downwardly moved.
    Type: Grant
    Filed: August 11, 1997
    Date of Patent: October 5, 1999
    Assignee: NGK Insulators, Ltd.
    Inventors: Minoru Imaeda, Akihiko Honda, Katsuhiro Imai, Yuichiro Imanishi, Nobuyuki Kokune, Shoji Sogo, Kazuaki Yamaguchi, Tetsuo Taniuchi
  • Patent number: 5951758
    Abstract: According to the present invention, in the growth of an oxide single crystal or a compound semiconductor single crystal such as GaAs single crystal by the CZ method or LEC method, the tendency of concave solid-liquid interface shape at the periphery of the growing crystal can be suppressed to prevent polycrystallization without localized heating of the solid-liquid interface, while controlling the diameter of the growing crystal even when using a crucible with a larger diameter, thus improving the yield of crystal on a commercial scale. In the invention, the end of a cylindrical body having an inner diameter of larger than the predetermined diameter of straight part of the growing crystal is immersed in the raw material melt or liquid encapsulant and the crystal is pulled while preventing the shape of the solid-liquid interface from becoming concave by controlling the rotation rate of at least one of a crucible holding the raw material melt, the growing crystal and cylindrical body.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: September 14, 1999
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Katsushi Hashio, Shin-ichi Sawada, Masami Tatsumi
  • Patent number: 5948160
    Abstract: The invention relates to a method for detecting torsional oscillations among abnormal oscillations occurring during the course of pulling of a single crystal, and also to a method for manufacturing a silicon single crystal using this method. Torsional oscillations are detected by detecting seam portions of a silicon single crystal being rotated with a camera device, memorizing time intervals of the signals outputted by detection of the seam portions, calculating an average value of the time intervals, comparing a time interval of freshly outputted signals with the average value, and deciding occurrence of torsional oscillations in the single crystal when the resulting deviation exceeds a predetermined value. When this method is adopted for pulling of a silicon single crystal, the single crystal is prevented from generating a dislocation and from dropping owing to the breakage at a neck portion thereof. Thus, the silicon single crystal can be manufactured with an improved yield and with a high efficiency.
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: September 7, 1999
    Assignee: Sumitomo Sitix Corporation
    Inventor: Shinichi Sakurada
  • Patent number: 5944892
    Abstract: A crystal growing system has a plurality of crystal growing stations which are each comprised of a crucible, furnace, vacuum chambers and related equipment which is continuously used during the actual crystal growing process. A central process control console is connected to each crystal growing station so that growing parameters for all stations can be controlled from a single location. A common server unit services all crystal growing stations. The server unit is movable so that it can be positioned at each station both prior to initiating crystal formation and subsequent to completing crystal formation in order to service the station before and after the crystal growing operation. The server unit comprises a movable support structure which can be rolled along a set of tracks to be positioned sequentially adjacent to each station. The server unit includes a main hoist constructed to move a receiving chamber, either alone or together with a transition chamber.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: August 31, 1999
    Assignee: General Signal Technology Corporation
    Inventor: Zhixin Li
  • Patent number: 5938836
    Abstract: This invention provides an apparatus and a method for manufacturing semiconductor single crystals, which enable a steady process of pulling up high-quality single silicon crystals to be easily performed during the growing of silicon single crystals by the CZ method aided by applying a Cusp magnetic field. Three facing homopolar magnets (hereinafter referred to as magnet) 1, 2, and 3 arc disposed outside the single-crystal pulling up chamber. The magnet 3 is located at the same height as the free surface of the melt 6 stored in a quartz crucible as the free surface of the melt 6 stored in a quartz crucible 5. Furthermore, the strength of the magnets 3 is set to be weaker than that of the magnets 1 and 2. The flux lines of the magnets 3 substantially pass through the quartz crucible 5 in the horizontal direction. However, the flux lines of the magnet 3 do not reach the silicon single crystal 7 being pulled up.
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: August 17, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Junsuke Tomioka, Hiroshi Inagaki, Katsura Yamamoto
  • Patent number: 5935322
    Abstract: In the process of forming-the shoulder in which the diameter of a crystal is gradually extended from a small seed crystal to a predetermined value, the largest width of a bright ring, which is formed in a boundary between the melt and the crystal pulled up from the melt, is measured, and an arc width of an arbitrary portion of the bright ring located before the largest width portion is measured. When the largest width of the bright ring has reached a predetermined value, a measured value of the arc width at the arbitrary position of the bright ring is used as a reference value, and after that, automatic control is conducted so that the measured value of the arc width can be close to the reference value.
    Type: Grant
    Filed: April 15, 1998
    Date of Patent: August 10, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Koichi Shimomura, Yoshinobu Hiraishi, Mitsunori Kawabata, Kentaro Nakamura
  • Patent number: 5935325
    Abstract: A weight control in diameter method by using a load cell is applied to a wire-single crystal silicon pulling mechanism, such that the weight of single crystal silicon can be correctly measured, thereby obtaining superior control in diameter and reducing the cost of manufacturing the single crystal silicon.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: August 10, 1999
    Assignee: Komatsu Electronic Metals, Co., Ltd.
    Inventors: Hideki Tsuji, Mitsunori Kawabata, Yoshinobu Hiraishi, Ryo Yamagishi
  • Patent number: 5919302
    Abstract: The present invention relates to single crystal silicon, in ingot or wafer form, which contains an axially symmetric region in which vacancies are the predominant intrinsic point defect and which is substantially free of agglomerated vacancy intrinsic point defects, wherein the first axially symmetric region comprises the central axis or has a width of at least about 15 mm, and a process for the preparation thereof.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: July 6, 1999
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Robert A. Falster, Joseph C. Holzer, Steve A. Markgraf, Paolo Mutti, Seamus A. McQuaid, Bayard K. Johnson
  • Patent number: 5888299
    Abstract: An apparatus and a method capable of automatically adjusting an initial position of the surface of a melt without an operator are provided. In a single crystal puller using a wire as a suspender for a seed crystal for growing a single crystal of silicon or the like according to the CZ method, a reference position of the seed crystal is detected, the wire is unwound to lower the end of the wire to a position higher by a distance W-X from the reference position and then pulled upward above said reference position to correct the wire for an extension due to the weight of a single crystal attached thereto. Also, the wire is left above a melt for about ten minutes to provide a constant amount of extension to the wire due to heat of the melt These operations are automatically performed.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: March 30, 1999
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Masahiko Urano, Atsushi Ozaki, Tomohiro Kakegawa, Hideki Nakano