Patents Examined by Felisa Garrett
  • Patent number: 5824149
    Abstract: An enclosing structure extends into a transition zone of a crystal growing system through which the growing crystal is pulled. One or more independent temperature control devices are secured to the inside surface of the enclosing structure, which control devices sense crystal temperature and supply to, or extract heat from, the crystal so that a carefully-controlled thermal gradient can be established either radially or longitudinally in the crystal. The temperature control devices may include temperature sensors that provide temperature information to a central control device connected to each temperature control device. The enclosing structure may have a hollow wall structure through which a heat exchange fluid, such as water, is passed to extract heat from the transition chamber and crystal. The temperature control apparatus may also be segmented so that each segment can be controlled independently of the remaining segments thereby permitting independent control to be effected at different crystal areas.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: October 20, 1998
    Assignee: Ferrofluidics Corporation
    Inventor: Zhixin Li
  • 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: 5824562
    Abstract: There are disclosed an opening filling apparatus and a method for manufacturing a semiconductor device by using the same. An opening of a semiconductor device is filled by using the filling apparatus comprising: a chamber having a rotation shaft, a motor, a plurality of plates arranged in a circular form centering at the rotation shaft, and a heater; and means for injecting gas. When the opening of a semiconductor device such as a trench or a contact hole is filled, filling material may move down by using the centrifugal force generated by rotating the substrate, to thereby fill the opening completely without a void.
    Type: Grant
    Filed: July 25, 1995
    Date of Patent: October 20, 1998
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Tai-su Park
  • Patent number: 5824150
    Abstract: A process and apparatus for forming an Al film of good quality according to the CVD method utilizing the reaction between alkyl aluminum hydride and hydrogen, which is an excellent deposited film formation process also capable of selective deposition of Al. Pressure in a deposition chamber is maintained from 10.sup.-3 to 760 Torr. Alkyl aluminum hydride and hydrogen gas are introduced at a partial pressure from 1.5.times.10.sup.-5 to 1.3.times.10.sup.-3 of the pressure in the chamber. Aluminum is deposited on a substrate in the chamber by heating the substrate sufficiently to decompose the alkyl aluminum hydride.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: October 20, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Nobuo Mikoshiba, Kazuo Tsubouchi, Kazuya Masu
  • Patent number: 5820672
    Abstract: A method for controlling oxygen-induced stacking faults (OISF) in a silicon crystal (12) grown according to the Czochralski silicon crystal growing technique includes the steps of forming a flared top portion (18) of the silicon crystal (12) to a predetermined diameter (20) and tapering (23) the silicon crystal (12) top portion (18) to produce a cylindrical portion (22) having a second predetermined diameter. The second predetermined diameter is smaller than the first predetermined diameter. Because of the inward taper (23) OISF concentrates in the flared top portion (18) of silicon crystal (12).
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: October 13, 1998
    Assignee: Texas Instruments Incorporated
    Inventors: Weldon J. Bell, H. Michael Grimes
  • Patent number: 5817173
    Abstract: The present invention relates to a method for forming crystal substrates on which can be easily formed spherical crystals which have superior crystal structure and little defect in shape. The present invention also relates to a method for making crystal substrates on which can be easily formed spherical crystals which have little defect in shape and from which impurities have been removed. Projections are formed integrally from a semiconductor crystal base, and flow regulating film is formed to cover the entire outer surface of the crystal base and a base portion of the projections. A heating beam is applied to the tips of the projections, and the end portions of the projections are melted. The surface tension of the melt and the melt regulation by the flow regulating film act to solidify the melt in a spherical shape, thus forming a spherical crystal.
    Type: Grant
    Filed: June 11, 1996
    Date of Patent: October 6, 1998
    Inventor: Josuke Nakata
  • Patent number: 5817172
    Abstract: For the solution growth, a solvent is used which is composed of a mixture of an oxide containing at least one member of those elements which constitute the oxide crystal and a halide containing at least one member of those elements which constitute the oxide crystal. The process enables the temperature of crystal growth to be lowered to a significant extent, avoids inclusions such as impure anionic elements from getting intruded into the oxide crystal, while retaining adequate crystal growth through solution growth, and affords, in spite of an atmospheric mode of crystal growth and with the pinning force of magnetic flux used to advantage, the same level of beneficial effects as in a mode of crystal growth at a low oxygen pressure.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: October 6, 1998
    Assignee: NGK Insulators, Ltd.
    Inventors: Yasuji Yamada, Yusuki Niiori, Yoshiaki Ito, Yutaka Yoshida, Izumi Hirabayashi
  • Patent number: 5817171
    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: May 31, 1996
    Date of Patent: October 6, 1998
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Masahiro Sakurada, Tomohiko Oota, Kiyotaka Takano, Masanori Kimura
  • 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: 5810925
    Abstract: A GaN single crystal having a full width at half-maximum of the double-crystal X-ray rocking curve of 5-250 sec and a thickness of not less than 80 .mu.m, a method for producing the GaN single crystal having superior quality and sufficient thickness permitting its use as a substrate and a semiconductor light emitting element having high luminance and high reliability, comprising, as a substrate, the GaN single crystal having superior quality and/or sufficient thickness permitting its use as a substrate.
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: September 22, 1998
    Assignee: Mitsubishi Cable Industries, Ltd.
    Inventors: Kazuyuki Tadatomo, Shinichi Watabe, Hiroaki Okagawa, Kazumasa Hiramatsu
  • Patent number: 5810923
    Abstract: The invention provides an oxide thin film in the form of an epitaxial film of the composition: Zr.sub.1-x R.sub.x O.sub.2-.delta. wherein R is a rare earth metal inclusive of Y, x=0 to 0.75, preferably x=0.20 to 0.50, formed on a surface of a single crystal silicon substrate. A rocking curve of the film has a half-value width of up to 1.50.degree.. The film has a ten point mean roughness Rz of up to 0.60 nm across a reference length of 500 nm. An epitaxial film of the composition ZrO.sub.2 is constructed by unidirectionally oriented crystals. When a functional film is to be formed on the oxide thin film serving as a buffer film, an adequately epitaxially grown functional film of quality is available.Particularly when the single crystal substrate is rotated within its plane, an oxide thin film of uniform high quality having an area as large as 10 cm.sup.2 or more is obtained.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: September 22, 1998
    Assignee: TDK Corporation
    Inventors: Yoshihiko Yano, Takao Noguchi, Katsuto Nagano
  • 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: 5797989
    Abstract: An apparatus for the continuous crystallization of polyester material is described, which apparatus can likewise be used for the drying of granules. The apparatus operates to improve the residence behavior of the material and the process. This is achieved by a circular apparatus having a gas inlet and gas outlet and product entry and product outlet, The product entry and product outlet are arranged concentrically and parallel to the axis of the apparatus. A product outlet device is arranged so that it is axially displaceable.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: August 25, 1998
    Assignee: Buehler AG
    Inventors: Hans Geissbuehler, Heinz Gasser
  • Patent number: 5797990
    Abstract: Orbital oscillations of the crystal ingot suspended in a cable in a Czochralski crystal puller are damped by mechanically connecting a high-temperature conductor to the ingot and generating a magnetic field in the vicinity of the conductor. The magnetic field induces an eddy current in the conductor when the ingot moves. The eddy current then interacts with the magnetic field to damp motion of the ingot. In one embodiment, the magnetic field generator is moved as the ingot grows to maintain the magnetic field in the vicinity of the conductor. In another embodiment, the strength of the magnetic field is adjusted dependent on the amplitude of the oscillations to conserve power.
    Type: Grant
    Filed: February 26, 1996
    Date of Patent: August 25, 1998
    Assignee: Ferrofluidics Corporation
    Inventor: Zhixin Li
  • Patent number: 5795382
    Abstract: A method for controlling oxygen precipitation (106) in a silicon crystal (12) grown according to the Czochralski silicon crystal growing technique which includes the steps of forming a cylindrical portion (22) of the silicon crystal (12) from a reservoir of molten silicon (24) according to the Czochralski silicon crystal growing technique. The method includes the steps of terminating the Czochralski silicon crystal growing technique by forming a first tapered portion (101) in silicon crystal (12) at a predetermined rate. A second tapered portion (102) includes a cascaded middle portion (108) that connects to the first tapered portion (101) and that concentrates oxygen precipitation (106) within cascaded middle portion (108) and away from the cylindrical portion (22) of silicon crystal (12). At least a third tapered portion (104) is formed for separating silicon crystal (12) from molten silicon (24).
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: August 18, 1998
    Assignee: Texas Instruments Incorporated
    Inventors: Weldon J. Bell, H. Michael Grimes
  • Patent number: 5795795
    Abstract: A method of fabricating a semiconductor device by the use of laser crystallization steps is provided. During these crystallization steps, an amorphous or polycrystalline semiconductor is crystallized by laser irradiation in such a way that generation of ridges is suppressed. Two separate laser crystallization steps are carried out. First, a laser irradiation step is performed in a vacuum, using somewhat weak laser light. Then, another laser irradiation step is performed in a vacuum, in the atmosphere, or in an oxygen ambient with intenser laser light. The first laser irradiation conducted in a vacuum does not result in satisfactory crystallization. However, this irradiation can suppress generation of ridges. The second laser irradiation step is performed in a vacuum, in the atmosphere, or in an oxygen ambient to achieve sufficient crystallization, but no ridges are produced.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: August 18, 1998
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Takamasa Kousai, Hongyong Zhang, Akiharu Miyanaga
  • Patent number: 5795383
    Abstract: A method and a mechanism for lifting a gas flow-guide cylinder of a crystal pulling apparatus are disclosed. The crystal pulling apparatus includes a crucible for accommodating a crystalline material and for melting the crystalline material through heating, and a gas flow-guide cylinder capable of being moved upward/downward above the crucible. The crystal pulling apparatus is operated to grow a single crystal from the crystalline material by a pulling method. When a solid crystalline material is to be placed in the crucible, the gas flow-guide cylinder is moved upward to thereby separate the bottom end of the gas flow-guide cylinder away from the top portion of the crucible. This prevents the crystalline material from coming into contact with the gas flow-guide cylinder.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: August 18, 1998
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Hideo Okamoto, Toshiharu Uesugi, Atsushi Iwasaki, Tetsuhiro Oda
  • Patent number: 5795384
    Abstract: The presently claimed invention relates to a method of producing, in large volumes and at low cost, transition metal carbide, nitride or carbonitride whiskers, preferably submicron, having excellent reinforcing properties. These whiskers are suitable for use as a reinforcement in a wide range of materials, including metals, intermetallics, plastics, ceramics and metallic bonded hard material. The basic idea is the use of a carbon source with a volatile part which volatiles at temperatures up to 1000.degree. C. Transition metal oxide or alkali compounds thereof in amounts to satisfy the stoichiometric requirements of the desired carbide or nitride is mixed with the carbon powder along with an alkali metal chloride powder as a volatilization agent for the metal and a catalyst for the whisker growth such as Ni or Co. The reactant powders are blended in some typical manner using a high speed blender so as to intimately mix them.
    Type: Grant
    Filed: July 20, 1995
    Date of Patent: August 18, 1998
    Assignees: Sandvik AB, Advanced Industrial Materials
    Inventors: Roy Tom Coyle, Jan Magnus Ekelund
  • Patent number: 5792255
    Abstract: In a single crystal manufacturing method by a horizontal magnetic field applied CZ method wherein coils are disposed interposing a crucible coaxially with each other, the coils constituting superconductive electromagnets of a magnetic field application apparatus and the silicon crystal is pulled from melt in the crucible while applying a horizontal magnetic field to the melt; an elavation apparatus capable of finely adjusting relative positions of the superconductive electromagnets and the crcucible in a vertical direction is disposed. The descent of a central portion Cm in a depth direction of the melt is canceled by elevating the crucible with the elevating apparatus, the descent being accompanied with proceeding of process of pulling the single crystal, thereby a coil central axis Cc of the superconductive electromagnets always passes through the central portion Cm or below this portion.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: August 11, 1998
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Eiichi Iino, Kiyotaka Takano, Masanori Kimura, Hirotoshi Yamagishi
  • Patent number: 5792253
    Abstract: A cylindrical alkali halide single-crystal-type ingot having an axis generally coinciding with the ?001! crystallographic direction is compressed in a heated dual platen press. To produce an approximately rectangular compressed ingot that is devoid of cracks and fissures at and adjacent the periphery, the surface of the ingot is flatted. For crystals having a face-centered lattice (e.g. NaI), the flat is parallel to the (100) crystallographic plane. For crystals having a body-centered lattice (e.g. CsI), the flat is parallel to the (110) crystallographic plane. The flat is placed on the lower platen of the press to properly orient the crystallographic structure of the ingot with respect to the direction of compression.
    Type: Grant
    Filed: July 22, 1996
    Date of Patent: August 11, 1998
    Assignee: Siemens Medical Systems, Inc.
    Inventors: Lev G. Eidelman, Olexy V. Radkevich