Including Heating Or Cooling Details (e.g., Shield Configuration) Patents (Class 117/217)
  • Patent number: 6285011
    Abstract: An electrical resistance heater for use in a crystal puller used for growing monocrystalline ingots according to the Czochralski method comprises a heating element sized and shaped for placement in the housing of the crystal puller for radiating heat within the housing. The heating element has heating segments arranged in a generally side-by-side relationship and electrically connected together. Each heating segment comprises a web and a flange projecting outwardly from the web in non-coplanar relationship therewith. This reduces the cross-sectional area of the heating segment for increasing the electrical resistance and power output of the heater while providing desired structural rigidity.
    Type: Grant
    Filed: October 12, 1999
    Date of Patent: September 4, 2001
    Assignee: MEMC Electronic Materials, Inc.
    Inventor: Carl F. Cherko
  • Patent number: 6261364
    Abstract: A system for growing high-quality, low-carbon-concentration single crystals which have an excellent gas-flow guiding function near the melt, containing 1) an inverted conical, flow-guide cover placed above and coaxially with a double-walled crucible, with its lower end located immediately above the surface of the melt and in the space between the outer surface of the single crystal to be grown and the inner surface of the sidewall of the inner crucible; 2) a short passage comprising a hole passing through the sidewall of the inner crucible at a position higher than the level of the melt; and 3) a flow guide cylinder placed above and coaxially with the double-walled crucible, with its lower end located immediately above the surface of the melt and in the space between the outer surface of the sidewall of the inner crucible and the inner surface of the sidewall of the outer crucible, all arranged in a furnace.
    Type: Grant
    Filed: September 1, 1998
    Date of Patent: July 17, 2001
    Assignees: Mitsubishi Materials Corporation, Mitsubishi Materials Silicon Corporation
    Inventors: Yoshiaki Arai, Keisei Abe, Norihisa Machida
  • Patent number: 6251184
    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: Grant
    Filed: May 26, 1999
    Date of Patent: June 26, 2001
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jae-gun Park
  • Patent number: 6238477
    Abstract: A process and device for the production of a single crystal of semiconductor material is by pulling the single crystal from a melt, which is contained in a crucible and is heated by a side heater surrounding the crucible. The melt is additionally heated, in an annular region around the single crystal, by an annular heating device which surrounds the single crystal and is positioned above the melt.
    Type: Grant
    Filed: March 7, 2000
    Date of Patent: May 29, 2001
    Assignee: Wacker Siltronic Gesellschaft für Halbleitermaterialien AG
    Inventors: Wilfried von Ammon, Erich Tomzig, Janis Virbulis
  • Patent number: 6217648
    Abstract: With relatively simple arrangement and at low cost, the present invention provides a single crystal pulling apparatus, by which it is possible to prevent a single crystal from being turned to polycrystal, to move the crystal itself smoothly and gently from a necking portion during pulling operation of the single crystal, and to reliably hold the single crystal even in case of trouble such as power suspension.
    Type: Grant
    Filed: April 21, 1999
    Date of Patent: April 17, 2001
    Assignee: Super Silicon Crystal Research Institute Corporation
    Inventor: Yutaka Shiraishi
  • Patent number: 6210477
    Abstract: The present invention relates to methods for pulling a single crystal wherein the induction of dislocation can be inhibited and a single crystal can be held safely. An apparatus for pulling a single crystal having a straightening vane in the shape of an inverted truncated cone whose upper and lower planes are removed, which is located between a crucible and a single crystal, is used. The gap between the lower end portion of the straightening vane and the surface of a melt filled into the crucible can be selected in the range of 30-200 mm. Where the gap is set large in the range of 30-200 mm, the temperature of the front portion of a seed crystal is raised till the difference in temperature between the front portion thereof and the melt (the range of 1380-1480° C.) becomes almost zero. The seed crystal is brought into contact with the melt, a neck is formed with being heated, and a main body is pulled from the melt.
    Type: Grant
    Filed: December 22, 1998
    Date of Patent: April 3, 2001
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Teruo Izumi, Hideki Watanabe
  • Patent number: 6197111
    Abstract: A heat shield for a crystal puller including an inner and an outer reflector. The inner and outer reflectors are spaced from each other an have reduced surface area in which they contact each other. Improved heat shielding of a growing crystal ingot reduces defects and permits a greater throughput of ingots produced by the crystal puller.
    Type: Grant
    Filed: February 26, 1999
    Date of Patent: March 6, 2001
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Lee Ferry, Yasuhiro Ishii
  • Patent number: 6183553
    Abstract: A method and apparatus for producing silicon single crystals with reduced contamination is disclosed. In one embodiment the structural components constructed of graphite and located in the hot zone of the crystal pulling apparatus have two protective layers. The first protective layer is applied directly to the graphite component. The second protective layer is a silicon layer and is applied on top of the first protective layer and covers the first layer. In a second embodiment, the structural components constructed of graphite and located in the hot zone of the crystal pulling apparatus have a single protective layer. The single protective layer is applied directly to the graphite and consists of a mixture of silicon carbide and silicon.
    Type: Grant
    Filed: June 15, 1998
    Date of Patent: February 6, 2001
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: John D. Holder, Steven M. Joslin, Harold W. Korb
  • Patent number: 6183556
    Abstract: A seed chuck for supporting a seed crystal for dipping in a hot melt has a main body including a dipping support formation for connection to a dipping apparatus and a seed support formation for supporting a seed crystal. A shield is coupled to the main body that insulates the seed crystal from cooling and heats the seed crystal with radiant energy emitted from the hot melt. The shield can be in the form of an insulating layer disposed against or inside of a portion of the seed chuck. In this case, the seed crystal is insulated from the cooler seed chuck and allowed to be warmed by the hot melt. The shield can also be a removable flange extending outwardly from the seed chuck and having an inverted cup shape or parabolic umbrella shape. In this case, the shield prevents cooling external gas flow from reaching the seed crystal while capturing and directing heat radiating from the hot melt onto the seed crystal.
    Type: Grant
    Filed: October 6, 1998
    Date of Patent: February 6, 2001
    Assignee: SEH-America, Inc.
    Inventors: Richard M. Aydelott, Clifford W. Groat
  • Patent number: 6179911
    Abstract: This invention provides a method and a apparatus capable of manufacturing single crystals with an oxygen density of less than 12×1017 atoms/cm3 or less than 10×1017 atoms/cm3, and wherein the oxygen density of the single crystal produced is uniformly distributed along its longitudinal axis. The electrical power inputted into the main heater 6 surrounding the quartz crucible 4 and the top heater 9 shaped like a reverse frustrated cone and disposed above the quartz crucible 4, is controlled to keep the temperature of the melt 5 in a preset range during the process of pulling up the single crystal silicon 10. When combining the main heater 6 and the top heater 9, the heat emitted from the main heater 6 can be kept small, and the heat load on the quartz crucible 4 and the amount of oxygen released from the quartz crucible 4 and dissloved into melt 5 can be reduced.
    Type: Grant
    Filed: October 25, 1999
    Date of Patent: January 30, 2001
    Assignee: Kamatsu Electronic Metals Co., Ltd.
    Inventors: Junsuke Tomioka, Hiroshi Inagaki, Fumitaka Ishikawa
  • Patent number: 6171395
    Abstract: The invention relates to a process for melting semiconductor material in a crucible which is located in a container, and is enclosed by a fixed heating device. The invention also relates to a heating device which is suitable for carrying out the process. The process is one wherein a heater of a displaceable heating device is lowered from a lock chamber above the container through an open shut-off valve into the container in the direction of the semiconductor material, and the semiconductor material is melted using the fixed heating device and the lowered heater. The heater is then raised back out of the container into the lock chamber after the semiconductor material has been melted. A door is provided in the lock chamber to allow the displaceable heater to be removed after the semiconductor material has been melted.
    Type: Grant
    Filed: December 1, 1998
    Date of Patent: January 9, 2001
    Assignee: Wacker Siltronic Gesellschaft f{umlaut over (u)}r Halbleitermaterialien AG
    Inventors: Wilfried von Ammon, Erich Tomzig, Paul Fuchs
  • 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: 6159283
    Abstract: Apparatus for measuring the mechanical strength of a neck portion of a silicon seed crystal used for growing a silicon crystal by the Czochralski method includes a seed chuck for holding the seed crystal of a test sample and an end of a wire hung from an upper hook. A crystal holder which holds the other end part of the test sample from below is tied to a lower hook with another wire to support the holder. The apparatus includes means for pulling the hook at a given rate, and measuring means for continuously measuring tensile load. Such apparatus and the method thereby provide accurate measurement of mechanical strength of the neck portion of the silicon seed crystal with good precision and reproducibility. A single crystal ingot is grown under conditions affording good balance of productivity and safety.
    Type: Grant
    Filed: March 12, 1999
    Date of Patent: December 12, 2000
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Isamu Harada, Michiaki Oda, Masaru Toyoshima, Toshinari Murai, Eiichi Iino
  • Patent number: 6153008
    Abstract: Device for pulling a silicon single crystal 1 includes an element 5 which annularly surrounds the single crystal growing at a crystallization boundary; and the element has a face 6 directed at the single crystal. The element surrounds the single crystal substantially level with the crystallization boundary 2 and has the property of reflecting heat radiation radiated by the single crystal and the similar melt or of generating and radiating heat radiation back to the lower part of the crystal close to the crystallization boundary. There is also a method for pulling a silicon single crystal, in which the single crystal is thermally affected using the element surrounding it.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: November 28, 2000
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien AG
    Inventors: Wilfried Von Ammon, Hans Olkrug, Erich Dornberger, Franz Segieth
  • Patent number: 6146459
    Abstract: Czochralski pullers are modified to grow perfect monocrystalline silicon ingots that are free of vacancy agglomerates and interstitial agglomerates, by modifying components of the Czochralski puller to produce a temperature gradient at the ingot-melt interface that is greater than about 2.5 degrees Kelvin per millimeter at the ingot axis and is also at least about equal to the temperature gradient at a diffusion length from the cylindrical edge of the ingot. By producing a temperature gradient at the ingot-melt interface that is greater than about 2.5 degrees Kelvin per millimeter at the ingot axis and that is also at least about equal to the temperature gradient at a diffusion length from the diffusion edge, an ingot-melt interface that is planar or is convex relative to the silicon melt may be produced. The ingot so pulled is sliced into a plurality of pure silicon wafers that may include point defects but that are free of vacancy agglomerates and interstitial agglomerates.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: November 14, 2000
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jae-gun Park
  • Patent number: 6136090
    Abstract: A method of producing a single crystal by Czochralski method by contacting a seed crystal with a melt in a crucible, and then pulling it slowly to grow a single crystal ingot, wherein a pulling condition is controlled according to a cumulative time of use of a heater surrounding the crucible. The pulling conditions to be controlled may induce the relative position of the heater and the crucible, the number of rotations of the crucible, the number of rotations of the crystal, or an atmosphere pressure in the furnace and a gas volume of flowing. Also described is a method of producing a silicon single crystal by CZ method wherein a dispersion of impurity concentration in the crystal can be reduced, and a single crystal can be produced stably.
    Type: Grant
    Filed: February 12, 1999
    Date of Patent: October 24, 2000
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Kenji Araki, Hideo Okamoto, Toshiharu Uesugi, Atsushi Iwasaki
  • Patent number: 6117234
    Abstract: The object of the present invention is to provide an apparatus and a method for preventing dropping of a single crystal having large diameter and heavy weight in a chamber with reduced pressure and for pulling it in reliable and safe manner. After a seed crystal 24a is immersed in Si melt in a quartz crucible 14, the seed crystal is pulled up, and a neck portion 1a with small diameter is formed under the seed crystal 24a, and a spherical constricted portion 1b is formed under the neck portion 1a, whereby a tip 23a of a single crystal support 23 is opened so that it does not come into contact with the constricted portion 1b under pulling operation.
    Type: Grant
    Filed: March 10, 1998
    Date of Patent: September 12, 2000
    Assignee: Super Silicon Crystal Research Institute Corp.
    Inventor: Hirotoshi Yamagishi
  • Patent number: 6117402
    Abstract: This invention provides a device for manufacturing single crystals provided with an after-cooler that causes an abrupt temperature gradient along the axis of the crystal being lifted. The device according to this invention can further increase the lifting speed of single crystals. The after-cooler (4) is disposed between the single crystal (5) being lifted and the heat-shield plate (1). Both the inner surface facing the single crystal (5) and the outer surface facing the heat-shield plate (1) of the after-cooler have a surface emissivity value larger than 0.6. Furthermore, the after-cooler (4) is made of cooling pipes or cooling jackets, and the surfaces of the after-cooler (4) are treated by oxidizing or nitriding so as to increase their emissivity values.
    Type: Grant
    Filed: April 6, 1999
    Date of Patent: September 12, 2000
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Toshirou Kotooka, Yoshiyuki Shimanuki, Makoto Kamogawa
  • Patent number: 6117230
    Abstract: A process for producing a silicon single crystal by the Czochralski method, utilizes a heater which is intended for heating a silicon-filled crucible and is arranged below the crucible. The process has energy delivered to the melt at least some of the time inductively using a coiled heater arranged under the crucible. The heater is in the form of a wound coil.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: September 12, 2000
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien AG
    Inventors: Wilfried Von Ammon, Erich Tomzig, Paul Fuchs, Yuri Gelfgat
  • Patent number: 6099641
    Abstract: A method and apparatus for pulling a single crystal by, for example, the Czochralski method where a melt is heated by heaters arranged around, or around and below a crucible. Auxiliary heaters are provided above the crucible to directly heat the melt to supplement the heaters arranged around, or around and below the crucible, so asto reduce the power of the heaters arranged around, or around and below the crucible. According to the method, a single crystal is pulled under the condition of the local highest temperature of a quartz crucible of 1600.degree. C. or less.
    Type: Grant
    Filed: August 11, 1999
    Date of Patent: August 8, 2000
    Assignee: Sumitomo Sitix Corporation
    Inventor: Naoki Ikeda
  • Patent number: 6093913
    Abstract: An electrical resistance heater for use in a crystal puller used for growing monocrystalline silicon ingots according to the Czochralski method comprises a heating element sized and shaped for disposition in the housing of the crystal puller around the crucible for applying heat to the crucible and silicon therein. The heating element includes heating segments connected together in an electric circuit. The segments have upper and lower sections and are arranged relative to each other so that when disposed around the crucible containing molten silicon the upper sections are disposed generally above a horizontal plane including the surface of the molten silicon and the lower sections are disposed generally below the horizontal plane. The upper sections are constructed to generate more heating power than the lower sections thereby to reduce a temperature gradient between the molten silicon at its surface and the ingot just above the surface of the molten silicon.
    Type: Grant
    Filed: June 5, 1998
    Date of Patent: July 25, 2000
    Assignee: MEMC Electronic Materials, Inc
    Inventors: Richard G. Schrenker, William L. Luter
  • Patent number: 6086671
    Abstract: A method for melting a silicon starting material can suppress silica (SiO2) from melting out from a quartz crucible wherein the silicon starting material is melted and can provide a high-quality silicon single crystal in a high yield. The growth method comprises melting the silicon starting material charged in the crucible while applying thereto a static magnetic field, contacting a seed crystal to a surface of the silicon melt, and pulling the seed crystal upwardly to solidify the contacted melt. The silicon starting material charged in the crucible, which is under melting, is applied with a static magnetic field such as a Cusp magnetic field, a horizontal magnetic field and/or a vertical magnetic field. The application can control heat convection occurring in the crucible during the course of the melting of the starting material, thereby obtaining a silicon single crystal having a reduced number of dislocation defects.
    Type: Grant
    Filed: September 1, 1998
    Date of Patent: July 11, 2000
    Assignee: Sumitomo Sitix Corporation
    Inventors: Souroku Kawanishi, Youichi Yamamoto
  • Patent number: 6080238
    Abstract: After whole raw material filled in a crucible is melted by plural heaters provided around the crucible, outputs of the heaters are lowered so that molten liquid is maintained at a predetermined temperature. A seed crystal is brought into contact with a surface of the molten liquid, and while a height of the surface of the molten liquid is being maintained in a heating region of a topmost heater, a pulling shaft is pulled up at a predetermined speed so that a single crystal is grown in a lower position of the seed crystal. At this time, in order that the pulled single crystal has required oxygen concentration during the pulling of the single crystal, a ratio of the output of the topmost heater to the outputs of all the heaters is set to a value calculated by R.sub.PW .gtoreq.0.88R.sub.T (R.sub.PW : output ratio of the topmost heater) based on the ratio R.sub.T of the height of the topmost heater to the height of the crucible.
    Type: Grant
    Filed: August 31, 1998
    Date of Patent: June 27, 2000
    Assignee: Sumitomo Sitix Corporation
    Inventor: Makoto Ito
  • Patent number: 6077348
    Abstract: The object of the present invention is to achieve reliable and safe pulling operation of a single crystal having large diameter and heavy weight in a chamber with reduced pressure. According to the present invention, a constricted portion is formed under a seed crystal, and a single crystal is pulled up by supporting the constricted portion, and a support base 30 is used, which has an opening 22, serving as a through-hole, and a slit 34, which leads from the opening to outer periphery of the support base, and a portion with larger diameter of the constricted portion is supported from below in linear contact manner. The support base 30 further comprises a recess 32, which leads to the opening 22, and it can be designed and selected to have such configuration as to suit the shape of the constricted portion. The support base 30 can be moved between a non-support position and a support position by operating a moving unit.
    Type: Grant
    Filed: March 10, 1998
    Date of Patent: June 20, 2000
    Assignee: Super Silicon Crystal Research Institute Corp.
    Inventor: Yutaka Shiraishi
  • 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: 6063189
    Abstract: A clamping portion 2 is suspended by wire cables 5. A linkage 3 connects the clamping portion 2 and a contacting portion 4 disposed below the clamping portion 2. One end of a circular-arc member 1 is pivotally supported by a swivel axis 33. The circular-arc member 1 is swiveled by guiding the contacting portion 4 to contact with the shoulder 63 of the crystal body 6.
    Type: Grant
    Filed: October 21, 1998
    Date of Patent: May 16, 2000
    Assignee: Komatsu Electric Metals Co., Ltd.
    Inventor: Yoshinobu Hiraishi
  • Patent number: 6059874
    Abstract: A process for reducing the load on a seed crystal during the pulling of a single crystal uses a pulling device. An adhesive bond is made between a conical section at the start of the single crystal and a retaining body. The load on the seed crystal is reduced by creating a tensile stress between the retaining body and the pulling device.
    Type: Grant
    Filed: August 18, 1998
    Date of Patent: May 9, 2000
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien AG
    Inventor: Wilfried Von Ammon
  • 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: 6042644
    Abstract: A single crystal pulling method includes the steps of: immersing seed crystal in a melt; growing single crystal around the seed crystal and reducing its diameter to remove dislocation in the single crystal; prior to forming a straight waist product portion of single crystal having a prescribed diameter, forming a straight waist holding portion having a diameter smaller than the prescribed diameter; holding the straight waist holding portion by using a single crystal holding device; and pulling the straight waist product portion while the straight waist holding portion is held. Preferably the step of forming the straight waist holding portion includes a step of varying a pulling speed to make unevenness in the surface thereof.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: March 28, 2000
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Shoei Kurosaka, Hiroshi Inagaki, Shigeki Kawashima, Junsuke Tomioka
  • Patent number: 6036776
    Abstract: This invention provides a single-crystal manufacturing device which can perform the lifting of single crystals at a high speed, allowing single crystals with uniform qualities along their axes can be obtained.The method for manufacturing single crystals according to this invention are achieved by using a single-crystal manufacturing device provided with a combination of a heat shield plate 1 and an after-cooler 21. The heat shield plate 1, the thickness of the lower portion of which is 2-6 times that of a conventional heat shield plate, surrounds the single crystal 7 being lifted. The after-cooler 21 covers the top surface of the rim 1a of the heat shield plate 1 and encompasses the single crystal 7 being lifted. The amount of cooling water supplied to the after-cooler 21 is slowly increased until the time the single crystal is lifted to a preset length, and then the amount of cooling water is kept constant.
    Type: Grant
    Filed: September 1, 1998
    Date of Patent: March 14, 2000
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Toshiro Kotooka, Yoshiyuki Shimanuki, Makoto Kamogawa
  • Patent number: 6022411
    Abstract: The object of the present invention is to prevent the single crystal during pulling operation from turning to polycrystal when the single crystal under pulling operation is gripped by a gripper and to achieve the gripping automatically. When a wire 1 is moved down to immerse a seed crystal 3 into surface of a Si melt 11 in a quartz crucible 10, arms 12 and 13 wait at such positions that tips do not come into contact with the Si melt 11, and tips of the gripping arm 12 are opened so that the tips are not brought into contact with a portion with larger diameter 5 during pulling operation. By pulling up the wire 1, a neck portion 4, a portion with larger diameter 5, a constricted portion 6, and a crystal main portion 7 are formed under the seed crystal 3. When a sensor 14 detects that upper surface of the portion with larger diameter 5 has come into contact with the tips of the contact/detecting arm 13 during pulling operation, tips of the gripping arm 12 are closed and grip the constricted portion 6.
    Type: Grant
    Filed: March 10, 1998
    Date of Patent: February 8, 2000
    Assignee: Super Silicon Crystal Research Institute Corp.
    Inventor: Makoto Kuramoto
  • Patent number: 6015460
    Abstract: A method and an apparatus for pulling a silicon monocrystal from a melt iudes the pulling of a conical portion in each case at the beginning and at the end of the monocrystal and the pulling of a cylindrical portion between the conical portions. In this method, the surface of the conical portion at the beginning of the monocrystal is shielded by a shielding means spaced apart from the monocrystal.
    Type: Grant
    Filed: March 13, 1998
    Date of Patent: January 18, 2000
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien AG
    Inventors: Erich Dornberger, Wilfried Von Ammon
  • Patent number: 6007625
    Abstract: This invention provides a method and a apparatus capable of manufacturing single crystals with an oxygen density of less than 12.times.10.sup.17 atoms/cm.sup.3 or less than 10.times.10.sup.17 atoms/cm.sup.3, and wherein the oxygen density of the single crystal produced is uniformly distributed along its longitudinal axis. The electrical power inputted into the main heater 6 surrounding the quartz crucible 4 and the top heater 9 shaped like a reverse frustrated cone and disposed above the quartz crucible 4, is controlled to keep the temperature of the melt 5 in a preset range during the process of pulling up the single crystal silicon 10. When combining the main heater 6 and the top heater 9, the heat emitted from the main heater 6 can be kept small, and the heat load on the quartz crucible 4 and the amount of oxygen released from the quartz crucible 4 and dissloved into melt 5 can be reduced.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: December 28, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Junsuke Tomioka, Hiroshi Inagaki, Fumitaka Ishikawa
  • 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: 5993902
    Abstract: An apparatus and a method for preventing buildup of silicon oxides and silicon carbides on the inner surface of exhaust sleeves utilized in Czochralski (Cz) silicon crystal pullers are provided. The apparatus and the method include the provision of a vapor impervious layer coated on the inner surface of an exhaust sleeve, and forming a barrier to silicon oxides and silicon carbides deposition on the inner surface, to prevent the buildup of silicon oxides and silicon carbides on the surface of exhaust sleeves, thereby allowing more uniform laminar flow of process gases in the Cz chamber and the exhaust sleeve, and extending the useful lifetime of exhaust sleeves.
    Type: Grant
    Filed: April 9, 1997
    Date of Patent: November 30, 1999
    Assignee: SEH America, Inc.
    Inventor: Gary Randolph Heid
  • Patent number: 5989341
    Abstract: A single crystal producing apparatus to be used for raising the single crystals by a CZ method. A cylindrical portion of a main chamber of the single crystal producing apparatus can be separated from the apparatus. Hot zone components can be retained within the cylindrical portion. After the pulling up operation, the cylindrical portion is separated from the apparatus with the hot zone components being engaged with within the cylindrical portion and is carried to another chamber. In another chamber, an overhauling, reproducing and assembling operations of the hot components can be conducted. In the single crystal producing apparatus, a cylindrical portion which goes through an assembling operation of the hot zone components in another chamber is engaged with the apparatus, and the next pulling up operation is conducted. Time required to the next pulling up operation is shortened. The dust amount within the pulling up chamber is reduced.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: November 23, 1999
    Assignee: Sumitomo Sitix Corporation
    Inventors: Munehiro Yasuda, Shinichi Sakurada
  • Patent number: 5972106
    Abstract: A device and method for producing single crystals by the Czohralski method can control the temperature distribution and thermal history of single crystals to improve the production efficiency and quality of single crystals. The device includes a cylinder coaxially surrounding a single crystal pulling rod, having an upper end airtightly connected to the ceiling of a pulling chamber and a lower end close to the surface of a melt in a crucible. A heat insulating element is attached to the lower end of the cylinder, and is surrounded by a surface of the crystal, the inside wall of the crucible and the surface of the melt. The heat insulating element is sized to occupy 30-95% by volume of the space above the melt, and the space has a height corresponding to the radius of the crystal.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: October 26, 1999
    Assignee: Shin-Etsu Handotai Co., LTD.
    Inventors: Tomohiko Ohta, Susumu Sonokawa, Satoshi Soeta, Yoshihiro Kodama
  • Patent number: 5968264
    Abstract: In method for manufacturing a silicon single crystal in accordance with a Czochralski method, during the growth of the silicon single crystal, pulling is performed such that a solid-liquid interface in the crystal, excluding a peripheral 5 mm-width portion, exists within a range of an average vertical position of the solid-liquid interface .+-.5 mm. There is also disclosed a method for manufacturing a silicon single crystal in accordance with the Czochralski method, wherein during the growth of a silicon single crystal, a furnace temperature is controlled such that a temperature gradient difference .DELTA.G (=Ge-Gc) is not greater than 5.degree. C./cm, where Ge is a temperature gradient (.degree.C./cm) at a peripheral portion of the crystal, and Gc is a temperature gradient (.degree.C./cm) at a central portion of the crystal, both in an in-crystal descending temperature zone between 1420.degree. C. and 1350.degree. C. or between a melting point of silicon and 1400.degree. C.
    Type: Grant
    Filed: July 2, 1998
    Date of Patent: October 19, 1999
    Assignee: Shin-etsu Handotai Co., Ltd.
    Inventors: Makoto Iida, Eiichi Iino, Masanori Kimura, Shozo Muraoka, Hideki Yamanaka
  • Patent number: 5968266
    Abstract: An apparatus for manufacturing a single crystal of silicon includes a crucible, a heater, electrodes, and a magnet. In addition to a plurality of heat generating portions and two main electrode portions, the heater has two or more auxiliary electrode portions. Two or more heater support members having an insulating property are further provided so as to support the heater through the auxiliary electrode portions. The number of heat generating portions which may be present between a heater support member and an electrode and between heater support members if adjacent to each other is equal to or less than 4. Each generating portion of the heater has a thickness of 25 mm or more. This structure makes it possible to produce a single crystal of silicon without causing breakage of a heater, even if a large electric current flows through the heater, even if a magnetic field of a high intensity is applied to a silicon melt in the crucible, and even if the heater has a large diameter.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: October 19, 1999
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Eiichi Iino, Masanori Kimura, Shozo Muraoka
  • Patent number: 5954875
    Abstract: An apparatus for pulling silicon single crystal comprises a main apparatus body, a crucible disposed therein and comprised of a quartz crucible part and a crucible protection part, a heating member disposed at the outside of the crucible therearound, a temperature keeping cylindrical body disposed at the outside of the heating member, and a heat insulating material disposed between the temperature keeping cylindrical body and the main apparatus body, in which at least an inside upper region of the temperature keeping cylindrical body and/or the crucible protection part made from a carbonaceous material is covered with a thermally decomposed carbon film.
    Type: Grant
    Filed: May 23, 1997
    Date of Patent: September 21, 1999
    Assignee: Ibiden Co., Ltd.
    Inventors: Koji Kato, Masayuki Sato, Takashi Takagi
  • Patent number: 5951753
    Abstract: A method for producing a silicon monocrystal has a growing monocrystal kept for a specified dwell time in the specified temperature range of from 850.degree. C. to 1100.degree. C. This dwell time for the growing monocrystal in the chosen temperature range is either greater than 250 min or less than 80 min. A device and a method, in which the cooling rate of the growing monocrystal is to be influenced, has a heat shield which is subdivided into adjacent annular zones between a lower rim and an upper rim. These adjacent zones differ in regard to each's thermal conduction and transparency to heat radiation.
    Type: Grant
    Filed: May 9, 1997
    Date of Patent: September 14, 1999
    Assignee: Wacker Siltronic Gesellschaft fur Halbleitermaterialien AG
    Inventors: Erich Dornberger, Hans Olkrug, Wilfried Von Ammon, Dieter Graf
  • Patent number: 5942032
    Abstract: A heat shield assembly is used in a Czochralski crystal puller for selectively shielding a monocrystalline ingot of semiconductor material to control the type and number density of agglomerated defects in the crystal structure of the ingot. The heat shield assembly has an upper heat shield connected to a lower heat shield. The upper and lower heat shields are connected to each other and slidingly connected to an intermediate heat shield. The lower heat shield is able to telescope up into the intermediate heat shield to minimize the profile of the heat shield assembly located within a crystal growth chamber of the crystal puller. However when needed to control formation of the monocrystalline ingot, the lower heat shield may be extended from the intermediate heat shield and project downwardly into the crystal puller crucible in close proximity to an upper surface of molten semiconductor source material in the crucible. A method employing the heat shield assembly is also disclosed.
    Type: Grant
    Filed: August 1, 1997
    Date of Patent: August 24, 1999
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Kyong-Min Kim, William L. Luter, Lee W. Ferry, Robert J. Braun, Srdjan Ilic, Mauro Dioda, Paolo Tosi, Marco Gobbo, Umberto Martini
  • Patent number: 5938842
    Abstract: A puller and method for crystal growth using the Czochralski technique in which a temperature profile and a history of thermal conditions of a growing crystal is controllable with ease and a good accuracy, which puller comprises a crucible containing raw material, heater for melting by heating the raw material and a heat insulating cylinder surrounding them, the heat insulating cylinder being cross-sectionally divided by an annular separation gap or gaps into parts and which method is applicable to growth of such a single crystal as of silicon, germanium, GaP, GaAs or InP in the puller. Methods for controlling a temperature profile and a history of thermal conditions of a growing crystal using the czochralski technique in the puller.
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: August 17, 1999
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Masahiro Sakurada, Tomohiko Oota, Kiyotaka Takano, Masanori Kimura
  • Patent number: 5935326
    Abstract: An cylindrical after-heater surrounding a single crystal being lifted and a cylindrical heat-retaining cylinder installed between the after-heater and the single crystal are provided above a reversed frustrated heat-shielding sleeve disposed near the melted liquid. The heat history of the single crystal can be controlled by adjusting the output of the after-heater and the location of the heat-retaining cylinder. By such an arrangement, rapid respond to the change of the heat environment in a furnace can be made and control of the temperature gradient of the single crystal can be achieved. The single crystal, throughout the whole length, is maintained in the range of from 1000.degree. C. to 1200.degree. C. for more than one hour during lifting operation.
    Type: Grant
    Filed: November 21, 1997
    Date of Patent: August 10, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Toshirou Kotooka, Toshimichi Kubota, Makoto Kamogawa, Yoshiyuki Shimanuki
  • Patent number: 5932008
    Abstract: In this invention, three equally spaced and "L" shaped hooks 6B are rotatably supported on the upper peripheral wall of the body 6A of the seed holder 6 at pivots 6E. A radiation screen 7 is hung at the front ends of the hooks 6B via three engaging fixtures 6C affixed on its upper rim. The radiation screen 7 shaped like a hollow trancated cone, is used to surround the lower end of the single-crystal being lifted from the quartz crucible 3 which is disposed within the main chamber 1. According to the apparatus for manufacturing a single-crystal which can perform the descending or ascending movements of the radiation screen, the setting operation, and the lifting operation consecutively and automatically. Therefor the apparatus can enhance the productivity and avoid any problems with process automation, furthermore, it is compatible with conventional equipment.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: August 3, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Yoshinobu Hiraishi, Koichi Shimomura
  • Patent number: 5928422
    Abstract: Regulating cylinder unit is divided into three parts, a third regulating cylinder shaped essentially like a cylinder and installed on the protection cylinder; a first regulating cylinder and a second regulating cylinder which are shaped like reversed truncated cones with different diameters and are capable of engaging with the third regulating cylinder. In addition, the second and third regulating cylinders are brought together in a preset ordering, that is, a flange formed at the outer peripheral rim of the upper end of the second regulating cylinder is engaged with a stepped portion of the third regulating cylinder, and a flange formed at the outer peripheral rim of the upper end of the first regulating cylinder is engaged with a flange formed at the inner peripheral rim of the lower end of the second regulating cylinder.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: July 27, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Teruhiko Uchiyama, Yoshiyuki Suzuki, Kazuyoshi Date
  • Patent number: 5922127
    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: September 30, 1997
    Date of Patent: July 13, 1999
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: William L. Luter, Lee W. Ferry
  • Patent number: 5911825
    Abstract: A heater is configured to reduce oxygen in the melt near the growing crystal is provided by defining a high temperature region in an upper region of the heater, above a melt surface of semiconductor material from which a crystal is grown. This effectively shifts the heat balance of the system upwards, and alters thermal convections of oxygen within the melt. Accordingly, the primary vehicle for transporting oxygen to the growing crystal is suppressed.
    Type: Grant
    Filed: September 30, 1997
    Date of Patent: June 15, 1999
    Assignee: SEH America, Inc.
    Inventors: Clifford W. Groat, Atsushi Iwasaki
  • Patent number: 5911826
    Abstract: An electrode is disposed at the lower end of a radiation screen. The electrode is made of single-crystal silicon. A circuit including a power source is established by contacting the electrode and the seed crystal to a silicon melt.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: June 15, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Yoshinobu Hiraishi, Masafumi Ura
  • Patent number: 5900059
    Abstract: This invention provides a method and apparatus for fabricating semiconductor single crystals. By using the method of this invention, the temperature gradient of the single crystal being lifted can be easily controlled. The as-grown defect density can be reduced, and it is possible to manufacture high quality semiconductor single crystals with high oxidation-film breakdown strength. A shield cylinder is used for surrounding the semiconductor single crystal 7 being lifted, the shield cylinder is made to be of the telescopic type and consists of a first shield duct 4, a second shield duct 5, a third shield duct 6. A wire 8 wrapping around a wind-up reel 10 is engaged with the third shield duct 6, and the shield cylinder can be driven to extend or retract by rotating the wind-up reel 10. An ascend and descend rod 3 is connected with the first duct 4, and the shield cylinder can be driven to move upward or downward by lifting or lowering the ascend and descend rod 3.
    Type: Grant
    Filed: April 14, 1998
    Date of Patent: May 4, 1999
    Assignee: Komatsu Electronic Metals Co., Ltd.
    Inventors: Yoshiyuki Shimanuki, Toshimichi Kubota, Toshirou Kotooka, Makoto Kamogawa