With Responsive Control Means Patents (Class 117/202)
  • Patent number: 5882402
    Abstract: A method and system for determining a diameter of a silicon single crystal being pulled from a silicon melt contained in a heated crucible. The melt has a surface with a meniscus visible as a bright area adjacent the pulled crystal. A camera generates an image of the interior of the crucible including a portion of the bright area adjacent the crystal. Image processing circuitry defines a central window region of the image having an elliptical shape at a position corresponding to an approximate center of the crystal and processes the image as a function of its pixel values to detect edges within the central window region. The image processing circuitry further groups the detected edges to define an object in the image corresponding to the crystal, determines a dimension of the defined object and determines an approximate diameter of the crystal as a function of the determined dimension of the defined object.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: March 16, 1999
    Assignee: MEMC Electronic Materials, Inc.
    Inventor: Robert H. Fuerhoff
  • Patent number: 5879451
    Abstract: An apparatus for measuring the weight of a crystal in a cable-type crystal pulling apparatus. A cable winding mechanism of the crystal pulling apparatus includes a guide pulley which is supported by a load plate and which changes the direction of the cable by 180 degrees, and a winding drum 8 which is disposed on a base plate and onto which the cable is wound. The load plate, on which a load due to pulling acts, is supported by a plurality of small-load load cells so that the load is equally distributed to the small-load load cells. Thus, the weight measuring apparatus can have a simple and low-cost structure, and the accuracy of measurement can be improved.
    Type: Grant
    Filed: December 11, 1996
    Date of Patent: March 9, 1999
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventor: Kouji Mizuishi
  • Patent number: 5868835
    Abstract: A recharger system including a feeder and a feed conduit recharge polycrystalline silicon granules into a crucible after a run or operation of growing a single crystal silicon rod by the Czochralski method, thereby to prepare for a next run of crystal growing. The amount of holdup or backed-up supply of the silicon granules in the feed conduit is detected by a sensor provided on the feed conduit. A smooth and high-rate feed of the silicon granules is ensured by controlling the feed rate of the silicon granules from the feeder to the feed conduit and/or a descending velocity of the crucible by signals generated in the sensor as a function of the amount of the holdup or backed-up supply in the feed conduit.
    Type: Grant
    Filed: August 7, 1997
    Date of Patent: February 9, 1999
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Naoki Nagai, Michiaki Oda, Seiichiro Ohtsuka, Isamu Harada
  • Patent number: 5858088
    Abstract: The winding drum of the cable-winding device is kept air-tight by an air-tight container. A lower elastic sealing member 1a is interposed between the air-tight container and the rotation table. The air-tight container, the lower elastic sealing member 1a, and the chamber are communicated with one another. The air-tight container and the chamber are filled with inert gases at less than atmospheric pressure. The rotation table, the weight sensors, the drive motor, the gear are disposed in the atmosphere. An arm is vertically installed on the rotation table. An upper elastic sealing member 1b is interposed between the end portion of the arm and the air-tight container. The upper elastic sealing member is communicated the interior of the air-tight container through a through hole. The arm support the top portion of the upper elastic sealing member.
    Type: Grant
    Filed: February 3, 1998
    Date of Patent: January 12, 1999
    Assignee: Komatsu Ltd.
    Inventors: Yoshinobu Hiraishi, Mitsunori Kawabata, Hideki Tsuji
  • Patent number: 5853479
    Abstract: An image of the meniscus ring (21) between the crystal (20) and the melt (4) is formed by optical means (12, 24) on a sensor, the signals of which yield the actual value for the diameter of the crystal. Two optical measuring devices are provided, the optical paths of which are defined by base points on the meniscus ring (21) and two planes which are offset by 90.degree. to each other and which are parallel to the main axis of the crystal and in tangential contact with the meniscus ring (21). The two optical paths are preferably set up to intersect, their intersection being in the viewing window.
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: December 29, 1998
    Assignee: Balzers und Leybold
    Inventors: Joachim Aufreiter, Dieter Bruss, Burkhard Altekruger
  • Patent number: 5851286
    Abstract: A crystal pulling apparatus is disclosed which employs the Czochralski method. The crystal pulling apparatus is operated while a heater for heating a material melt in a crucible is controlled by the main controller of a main system. When maintenance of a heating state is disabled for some reason, a relay of a signal changeover circuit is switched so as to maintain the heating state under control of the backup controller of a backup system, thereby maintaining the material melt in a molten state. Thus, even when it becomes impossible for the main system to heat the material melt within the crucible, the material melt can be prevented from becoming solidified.
    Type: Grant
    Filed: December 11, 1996
    Date of Patent: December 22, 1998
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Atsushi Ozaki, Masahiko Urano, Isamu Harada, Tomohiro Kakegawa, Hideki Nakano
  • Patent number: 5849076
    Abstract: Barrel reactor apparatus for chemical vapor deposition of a material on a semiconductor wafer having a cooling system which protects the semiconductor wafers from metals contamination caused by degradation of metallic surfaces of the barrel reactor. Degradation is caused by water reacting with other substances (e.g., HCl) in the barrel reactor. The cooling system has a controller which monitors the operational state of the barrel reactor and selects an operating setpoint based on the detected operational condition. As a result, the metallic surfaces of the barrel reactor are kept cool during operation to retard corrosive chemical reaction rates, and kept warmer than would be otherwise possible when the barrel reactor is not operating to prevent adsorption of water by and condensation of water onto the metallic surfaces.
    Type: Grant
    Filed: July 26, 1996
    Date of Patent: December 15, 1998
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Eric Lee Gaylord, Charles Herman Mueller
  • Patent number: 5846318
    Abstract: Method and system for use with a Czochralski crystal growing apparatus. The crystal growing apparatus has a heated crucible for melting solid silicon to form a melt from which the single crystal is pulled. The melt has an upper surface above which unmelted silicon is exposed until melted. A camera generates images of a portion of the interior of the crucible. Each image includes a plurality of pixels and each pixel has a value representative of an optical characteristic of the image. An image processor processes the images as a function of the pixel values to detect edges in the images and groups the detected edges as a function of their locations in the images to define objects in the images. The defined objects each include one or more pixels and at least one of the defined objects is representative of a portion of solid silicon which is visible on the melt surface.
    Type: Grant
    Filed: July 17, 1997
    Date of Patent: December 8, 1998
    Assignee: MEMC Electric Materials, Inc.
    Inventor: Massoud Javidi
  • Patent number: 5843228
    Abstract: The invention is directed to preventing meltdown of conductive metal electrodes 5, 5 used to supply current to a heater 104 of a crucible 103. A single crystal pulling apparatus comprises: the heater 104 which encircles the crucible 103, and the pair of electrodes 5, 5, respectively threaded to a pair of graphite intermediate electrodes 6 of the heater 104, and a voltage source 9 for supplying power to the pair of electrodes 5, 5. A switch 11 switches the power on and off. A watthour meter 10a, continuously measures the current flowing through the heater 104. Investigation by the present inventors showed that in the case of a crack 8 in a lower portion of the intermediate electrode 6, minute fluctuations occurred in the measured value of the current, arising from an electric discharge phenomena in the crack 8 prior to meltdown of the electrodes 5, 5.
    Type: Grant
    Filed: April 1, 1997
    Date of Patent: December 1, 1998
    Assignees: Mitsubishi Materials Silicon Corporation, Mitsubishi Materials Corporation
    Inventors: Masao Saitoh, Daisuke Wakabayashi, Takashi Atami, Hisashi Furuya
  • Patent number: 5827366
    Abstract: In a Czochralski monocrystalline silicon growing apparatus for growing a silicon monocrystalline by pulling up a crystal seed by a wire in a growing furnace, a magnetic ring is mounted on the silicon monocrystal, and an electromagnet is fixed to the growing furnace for pulling up the magnetic ring.
    Type: Grant
    Filed: November 22, 1996
    Date of Patent: October 27, 1998
    Assignee: NEC Corporation
    Inventor: Masahito Watanabe
  • Patent number: 5824153
    Abstract: An apparatus for holding a single-crystal semiconductor ingot which is stored in a pulling chamber of a single-crystal semiconductor pulling apparatus is disclosed. The apparatus includes a spindle; a base installed on the spindle and movable along the spindle; a pair of arms for holding the single-crystal semiconductor ingot; means for driving the arms; a pair of sensors for detecting the distance between the ingot and the arms; and a controller for driving the arms to the ingot according to the sensors; when each of the arms is detected to have a predetermined distance from the ingot, the controller stopping the movement of the arm; when both the arms have the predetermined distance to the ingot, the controller driving simultaneously both the arms to the ingot surface, thereby holding the ingot.
    Type: Grant
    Filed: December 10, 1996
    Date of Patent: October 20, 1998
    Assignee: Komatsu Electronic Metals Co., Ltd
    Inventors: Ayumi Suda, Yoshinobu Hiraishi, Koichi Shimomura
  • Patent number: 5817176
    Abstract: The present invention relates to an apparatus for preparing a single crystal of silicon by which a high-quality single crystal of silicon can be prepared by changing the rotation rate of a crucible or a seed and a process for preparing a single crystal of silicon thereby. As compared with a conventional apparatus employing Czochralski method, which comprises a rotating axis of seed, a seed, a crucible, a heater, a rotary axis of crucible, a chamber and an adiabatic layer, the apparatus of the present invention is characterized by the improvement comprising means for controlling the rotation rate of the crucible or the seed, each of which consists of a D.C. voltage, a function generator, a voltage summing circuit and a stepping motor.
    Type: Grant
    Filed: April 17, 1996
    Date of Patent: October 6, 1998
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Hyung-Jin Sung, Jung-Il Choi
  • Patent number: 5814150
    Abstract: In order to form a single-crystalline thin film on a polycrystalline substrate using plasma CVD, a downwardly directed mainly neutral Ne atom current is formed by an ECR ion generator (2). A reaction gas such as silane gas which is supplied from a reaction gas inlet pipe (13) is sprayed onto an SiO.sub.2 substrate (11) by an action of the Ne atom current, so that an amorphous Si thin film is grown on the substrate (11) by a plasma CVD reaction. At the same time, a part of the Ne atom current having high directivity is directly incident upon the substrate (11), while another part thereof is incident upon the substrate (11) after its course is bent by a reflector (12). The reflector (12) is so set that all directions of the parts of the Ne atom current which are incident upon the substrate (11) are perpendicular to densest planes of single-crystalline Si.
    Type: Grant
    Filed: February 7, 1996
    Date of Patent: September 29, 1998
    Assignees: Neuralsystems Corporation, Mega Chips Corporation
    Inventors: Toshifumi Asakawa, Masahiro Shindo, Toshikazu Yoshimizu, Sumiyoshi Ueyama
  • Patent number: 5800612
    Abstract: A single-crystal semiconductor pulling apparatus improves the crystallization rate by reinforcing the physical strength of the Dash's neck portion, and eliminate the process time difference depending on the experiences of operators. The single-crystal semiconductor pulling apparatus, which is according to the Czochralski method, includes controller for automatically controlling the pulling rate of a seed crystal and a melt temperature. The controller modifies a target value of a diameter of a crystal grown from the seed which is immersed from a first value to a second value. The first value is for ensuring dislocation-free state, while the second value is for retaining physical strength of the crystal. Furthermore, the controller is provided with the function of judging the crystal to be in dislocation-free state.
    Type: Grant
    Filed: February 6, 1997
    Date of Patent: September 1, 1998
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Koichi Shimomura, Yoshinobu Hiraishi, Taizou Miyamoto
  • Patent number: 5772758
    Abstract: Methods and apparatus are provided for monitoring deposition and pre-deposition characteristics such as the growth rates, oxide desorption, surface reconstruction, anion surface exchange reaction and smoothness of the surface of rotating substrates in near real-time during molecular beam epitaxy by processing the data in the time domain and for controlling a deposition apparatus in near real-time.
    Type: Grant
    Filed: February 15, 1996
    Date of Patent: June 30, 1998
    Assignee: California Institute of Technology
    Inventors: Douglas A. Collins, Thomas C. McGill, George O. Papa
  • Patent number: 5755877
    Abstract: In an extremely thin hetero-epitaxial growth film less than 1 .mu.m, the thin film can be grown at high precision by controlling the growth conditions. The method of growing a thin film on a semiconductor substrate comprises the steps of: forming a semiconductor thin film on a surface of a semiconductor substrate; allowing X-rays to be incident upon the thin film now being grown; measuring fluorescent X-rays emitted from the thin film now being grown in accompany with the application of the X-rays; and controlling growth conditions of the thin film on the basis of the measured values.
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: May 26, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takanobu Kamakura, Norihiko Tsuchiya
  • Patent number: 5746828
    Abstract: A crystal-pulling apparatus incorporates a temperature sensor and an adjustable radiation shield. The temperature sensor measures temperatures of a melt surface adjacent to a solidification interface between a crystal and the melt. The radiation shield regulates radiational cooling of the melt. A control system adjusts the radiation shield in response to changes in the measured temperature of the melt for enhancing dislocation-free growth of the crystal.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: May 5, 1998
    Assignee: General Signal Corporation
    Inventor: Anatoli S. Boulaev
  • Patent number: 5725661
    Abstract: An equipment for producing silicon single crystals based on an MCZ method, which enables an operator to be protected from dangerous exposure to magnetic field without involving increase in the size of the silicon single crystal production equipment. In the silicon single crystal production equipment based on the MCZ method, a growth furnace control apparatus for control of a pulling apparatus is located away from the pulling apparatus by a predetermined distance so that the intensity of magnetic field immediately close to the growth furnace control apparatus can become 300 gausses or less. A monitoring camera for observing the growing condition of the silicon single crystal is mounted to a window 5a of a growth furnace to be operatively connected to a monitor of the growth furnace control apparatus and to cause the growth furnace control apparatus to control the pulling apparatus on a remote control basis.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: March 10, 1998
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Izumi Fusegawa, Toshiro Hayashi, Tomohiko Ohta, Masayuki Arai
  • Patent number: 5723337
    Abstract: A method for measuring and controlling the oxygen concentration in silicon melts which are contained in a silica glass crucible or which can be touched by a silica glass surface can especially be used for achieving a defined, uniform axial and radial oxygen concentration in a growing silicon crystal. The measurement of the oxygen concentration is realized by an electrochemical solid ionic sensor dipped into the melt; the voltage is measured between the sensor and the growing silicon crystal. The oxygen concentration in the melt is controlled by applying a voltage between crystal and silica glass crucible. The apparatus for putting the method into practice includes an electrochemical solid ionic sensor formed of a silica glass tube which encloses a metal/metal oxide mixture, contacted by a metal wire.
    Type: Grant
    Filed: August 7, 1995
    Date of Patent: March 3, 1998
    Assignee: Georg Muller
    Inventors: Georg Muller, Rainer Marten, Albrecht Seidl
  • Patent number: 5683507
    Abstract: An apparatus for growing single-polytype, single crystals of silicon carbide utilizing physical vapor transport as the crystal growth technique. The apparatus has a furnace which has a carbon crucible with walls that border and define a crucible cavity. A silicon carbide source material provided at a first location of the crucible cavity, and a monocrystalline silicon carbide seed is provided at a second location of the crucible cavity. A heat path is also provided in the furnace above the crucible cavity. The crucible has a stepped surface that extends into the crucible cavity. The stepped surface has a mounting portion upon which the seed crystal is mounted. The mounting portion of the stepped surface is bordered at one side by the crucible cavity and is bordered at an opposite side by the furnace heat path. The stepped surface also has a sidewall that is bordered at one side by and surrounds the furnace heat path.
    Type: Grant
    Filed: September 5, 1995
    Date of Patent: November 4, 1997
    Assignee: Northrop Grumman Corporation
    Inventors: Donovan L. Barrett, Raymond G. Seidensticker, deceased, Richard H. Hopkins
  • Patent number: 5665159
    Abstract: System and method for determining the diameter of a silicon crystal being pulled from a silicon melt for controlling a silicon crystal growing apparatus. The melt has a surface with a meniscus which is visible as a bright ring adjacent the crystal. A camera generates an image pattern of a portion of the bright ring adjacent the crystal. Image processing circuitry detects a characteristic of the image pattern and defines an edge of the bright ring as a function of the detected characteristic. The image processing circuitry further defines a generally circular shape including the defined edge of the bright ring. The diameter of the crystal is then determined based on the diameter of the defined shape for use in controlling the crystal growing apparatus.
    Type: Grant
    Filed: March 21, 1996
    Date of Patent: September 9, 1997
    Assignee: MEMC Electronic Materials, Inc.
    Inventor: Robert H. Fuerhoff
  • Patent number: 5660629
    Abstract: An apparatus for precisely detecting the diameter of the single-crystal material which is fabricated by a continuously charged method is disclosed. Variables such as the crucible raising amount, the material charging amount and the weight of a growing single crystal can be detected by conventional detecting apparatus. A present melt surface position is obtained by initial melt surface position+the crucible raising amount +(material charging amount/crucible area)-(weight of the single-crystal/crucible area) and then provided to a diameter control apparatus. The sensing angle with respect to the initial melt surface position 3a is .theta.. The height from initial melt surface position 3a to one-dimensional image sensor 2 is h. The horizontal distance between the scanning line and the one-dimensional image sensor is r. When the melt surface falls by a distance of a .DELTA.h from position 3a to position 3b, the adjusted sensing angle .theta.' can be obtained from .theta.'=cos.sup.-1 [(h+.DELTA.h)/{(h+.DELTA.h).
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: August 26, 1997
    Assignee: Kamatsu Electronic Metals Co., Ltd.
    Inventors: Yutaka Shiraishi, Yihao Chang
  • Patent number: 5656078
    Abstract: System for determining the diameter of a silicon crystal being pulled from a silicon melt for controlling a silicon crystal growing apparatus. The melt has a planar surface including a meniscus that is visible as a bright ring adjacent the crystal. A camera positioned above the melt surface and away from the crystal includes an image plane that is generally parallel to the melt surface and responsive to light from the bright ring for generating an image pattern of a portion of the bright ring. As such, the camera compensates for distortion of the image pattern caused by the position of the camera relative to the crystal. Image processing circuitry detects a characteristic of the image pattern and defines an edge of the bright ring as a function of the detected characteristic. The image processing circuitry further defines a generally circular shape including the defined edge of the bright ring.
    Type: Grant
    Filed: November 14, 1995
    Date of Patent: August 12, 1997
    Assignee: MEMC Electronic Materials, Inc.
    Inventor: Robert H. Fuerhoff
  • Patent number: 5643540
    Abstract: Apparatus for growing protein crystals under microgravity environment includes a plurality of protein growth assemblies stacked one above the other within a canister. Each of the protein growth assemblies includes a tray having a number of spaced apart growth chambers recessed below an upper surface, the growth chambers each having an upstanding pedestal and an annular reservoir about the pedestal for receiving a wick and precipitating agents. A well is recessed below the top of each pedestal to define a protein crystal growth receptacle. A flexible membrane is positioned on the upper surface of each tray and a sealing plate is positioned above each membrane, each sealing plate having a number of bumpers corresponding in number and alignment to the pedestals for forcing the membrane selectively against the upper end of the respective pedestal to seal the reservoir and the receptacle when the sealing plate is forced down.
    Type: Grant
    Filed: February 27, 1995
    Date of Patent: July 1, 1997
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Daniel C. Carter, Timothy E. Dowling
  • Patent number: 5637146
    Abstract: A method for the growth of semiconducting nitrides, such as GaN, InN, AlN, and their alloys, in an ultra-high vacuum chamber, wherein low energy atomic nitrogen is generated by a plasma-excited radical atom source, the atom beam is introduced to the heated substrate within a short distance, other gaseous reactants and dopants, such as TMGa, TMIn, TMAj, DEZn, CP.sub.2 Mg, SiH.sub.4, and similar organmetallic and hydride sources, are injected from a circular injector located between the substrate and the atom source, and therefore large area epitaxy with high growth rate is obtained.
    Type: Grant
    Filed: March 30, 1995
    Date of Patent: June 10, 1997
    Assignees: Saturn Cosmos Co., Ltd., Jen-Inn Chyi
    Inventor: Jen-Inn Chyi
  • Patent number: 5598260
    Abstract: An apparatus and method for optically monitoring the output of an effusion cell during the MBE process where resonant radiation is guided through an optical radiation guide across the output orifice of the effusion cell to determine the atomic flux according to the concentration and absorbance of the resonant radiation at the output orifice of the effusion cell.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 28, 1997
    Assignee: Hughes Aircraft Company
    Inventors: Peter D. Brewer, Gregory L. Olson
  • Patent number: 5587015
    Abstract: An apparatus for production of single crystal oxide films by liquid-phase epitaxy comprises an insulating core tube with an external high frequency heating means, an electroconductive cylindrical member having openings at both ends and being arranged in the core tube, and a crucible made of an electroconductive material and coaxially arranged in the cylindrical member.
    Type: Grant
    Filed: April 6, 1995
    Date of Patent: December 24, 1996
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Masaru Fujino, Hiroshi Takagi
  • Patent number: 5578284
    Abstract: A silicon single crystal prepared by the Czochralski method including a neck having an upper portion, an intermediate portion, and a lower portion. The upper portion contains dislocations. The intermediate portion is between the upper and lower portions. A majority of the intermediate and lower portions has a diameter greater than 10 millimeters, and the lower portion is free of dislocations. The crystal also includes an outwardly flaring segment adjacent the lower portion of the neck, and a body adjacent the outwardly flaring segment.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 26, 1996
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Sadasivam Chandrasekhar, Kyong-Min Kim
  • Patent number: 5556465
    Abstract: A method and apparatus in Molecular Beam Epitaxy (MBE) in order to grow thin films. The substrate is attached to the rotatable manipulator and its normal will be aligned parallel to the rotation axis in vacuum for providing a real time information on the growth parameters by ellipsometry. The apparatus includes a rotatable manipulator head where the substrate is attached to, and aligning elements to align the substrate normal sufficiently parallel to the rotation axis of the manipulator in vacuum.
    Type: Grant
    Filed: September 15, 1994
    Date of Patent: September 17, 1996
    Assignee: DCA Instruments Oy
    Inventor: Tapani Levola
  • Patent number: 5552127
    Abstract: A biological macromolecular substances crystallization apparatus comprises a plate-like base, a lid having a concavity which defines an experimental vessel for crystallizing biological macromolecular substances when the lid is put on the base, a groove formed in the base of the experimental vessel for holding a first specimen solution for crystallizing biological macromolecular substances, a trench-like groove formed in the base of the experimental vessel for holding a second specimen solution for crystallizing biological macromolecular substances, tight sealing means for tightly closing the experimental vessel, a plug which is provided in the concavity in the lid, and which is pressed to cover said grooves and to separate said groove from said trench-like groove, and a valve which is provided in the concavity in the lid, and which equalizes an internal pressure in the experimental vessel to an external pressure.
    Type: Grant
    Filed: May 2, 1995
    Date of Patent: September 3, 1996
    Assignee: Fujitsu, Ltd.
    Inventor: Koji Asano
  • Patent number: 5540183
    Abstract: An apparatus for zone-melting recrystallization of semiconductor films on semiconductor substrates includes a heater disposed opposite the front surface of a semiconductor substrate and moving across the semiconductor substrate at a uniform rate. The heater may be a strip heating element covered with an insulating and refractory material radiating less heat than the strip heating element. Since heat emitted from surfaces of the heating element except the surface opposite the substrate is intercepted by the insulating and refractory film, the width of the molten zone produced in the semiconductor film is reduced.
    Type: Grant
    Filed: March 15, 1994
    Date of Patent: July 30, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Mikio Deguchi, Hideo Naomoto, Satoshi Arimoto
  • Patent number: 5529015
    Abstract: An ampoule failure system for use in material processing furnaces comprising a containment cartridge and an ampoule failure sensor. The containment cartridge contains an ampoule of toxic material therein and is positioned within a furnace for processing. An ampoule failure probe is positioned in the containment cartridge adjacent the ampoule for detecting a potential harmful release of toxic material therefrom during processing. The failure probe is spaced a predetermined distance from the ampoule and is chemically chosen so as to undergo a timely chemical reaction with the toxic material upon the harmful release thereof.The ampoule failure system further comprises a data acquisition system which is positioned externally of the furnace and is electrically connected to the ampoule failure probe so as to form a communicating electrical circuit. The data acquisition system includes an automatic shutdown device for shutting down the furnace upon the harmful release of toxic material.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: June 25, 1996
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Dale A. Watring, Martin L. Johnson
  • Patent number: 5476064
    Abstract: The density of a melt precisely represents the stability of the melt, so that the initiation of pulling-up operation can be determined on the basis of the changing rate of the density. The pulling-up operation may be started when the density becomes constant, or when the changing rate of the density with respect to the temperature becomes smaller. Since the melt or clusters do not include different minute structures, an obtained single crystal is of high quality free from minute faults or dislocations.
    Type: Grant
    Filed: March 18, 1994
    Date of Patent: December 19, 1995
    Assignees: Research Development Corporation of Japan, Hitoshi Sasaki, Kazutaka Terashima
    Inventors: Hitoshi Sasaki, Eiji Tokizaki, Kazutaka Terashima, Akira Nagashima, Shigeyuki Kimura
  • Patent number: 5472505
    Abstract: An apparatus for monitoring a film growth is disclosed, in which, when a crystalline thin film is grown by applying an MOCVD (metalorganic chemical vapor deposition method), the variation of the thickness and composition due to certain factors can be detected with real time during the film growing process, and an in-situ adjustment is possible. As the optical detector for detecting two sets of reflected beams which are reflected from the film, a silicon detector and a germanium detector are used, the former being suitable for detecting short wavelength laser beams, and the latter being suitable for detecting long wavelength laser beams. Thus two different wavelengths are detected with real time, thereby measuring the thickness and composition of the film.
    Type: Grant
    Filed: December 19, 1994
    Date of Patent: December 5, 1995
    Assignee: Electronics & Telecommunications Research Institute
    Inventors: Bun Lee, Dug-Bong Kim, Jong-Hyeob Baek
  • Patent number: 5454347
    Abstract: A laser-beam annealing apparatus that provides reliable, continuous control of the intensity of the laser beam used to perform the annealing process.
    Type: Grant
    Filed: July 2, 1993
    Date of Patent: October 3, 1995
    Assignees: Agency of Industrial Science & Technology, Ministry of International Trade & Industry
    Inventors: Hajime Shibata, Yunosuke Makita, Kawakatsu Yamada, Yutaka Uchida, Saburoh Satoh
  • Patent number: 5450814
    Abstract: A plurality of shield blades 31 for defining an opening 25 surrounding a single crystal 15 are provided between a melt 14 received in a crucible 10 and a screen 30. The shield blades 21 are carried by operation rods 23 so as to make the gap between the inner edges of the shield blades 23 and the surface of the single crystal 15 constant. Since crystal growth continues under the same condition from the beginning to the end, an obtained single crystal 15 is free from defects such as dislocations and excellent in homogenieity.
    Type: Grant
    Filed: October 14, 1993
    Date of Patent: September 19, 1995
    Assignees: Research Development Corporation of Japan, Yutaka Shiraishi, Kazutaka Terashima
    Inventors: Yutaka Shiraishi, Kazutaka Terashima
  • Patent number: 5410983
    Abstract: A crystal growth device is disclosed comprising a crucible in the cavity of which a crystallization reaction may take place to make possible the automatic and accurate observation of crystallization in miniaturized installation.
    Type: Grant
    Filed: April 29, 1991
    Date of Patent: May 2, 1995
    Assignee: Societe Anonyme dite: Aerospatiale Societe Nationale
    Inventor: Christian Gamelin
  • Patent number: 5396863
    Abstract: Installation for the crystallization of an inorganic substance in a crystal slurry, by desupersaturation of a supersaturated solution, the installation comprising a crystallization chamber which has a vertical axis and is divided into a central zone (4) and an annular zone (5), a device (9, 10) designed to bring about a vertical translation of the slurry in the central zone (4) and a translation in the opposite direction in the annular zone (5), a device (8) for withdrawing slurry, comprising a tube (23, 24) which opens into one of the abovementioned zones, a member (14) for mechanical shearing of the slurry, comprising, a disc (17) carrying a ring of shearing teeth (19), and a tube (6, 31) passing through the cover (30) and serving to introduce anhydrous sodium carbonate, the tube (31) having a prolongation inside the crystallization chamber, over which prolongation a film of water is caused to circulate.
    Type: Grant
    Filed: March 9, 1993
    Date of Patent: March 14, 1995
    Assignee: Solvay (Societe Anonyme)
    Inventors: Leon Ninane, Claude Breton