Processes Of Growth From Liquid Or Supercritical State Patents (Class 117/11)
  • Patent number: 6106609
    Abstract: Nanocrystalline semiconductors are synthesized within a bicontinuous cubic atrix 10. The nanocrystalline particles 12 may then be end-capped 18 with a dispersant to prevent agglomeration. One typical nanocrystalline semiconductor compound made according to the present invention is PbS. Other IV-VI semiconductors may be produced by the method of the present invention. The method of this invention may also be used to produce doped semiconductors.
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: August 22, 2000
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Jianping Yang, Banahalli R. Ratna
  • Patent number: 6074476
    Abstract: A system and method for forming spherical semiconductor crystals is disclosed. The system includes a receiver tube 18 for receiving semiconductor granules 104. The granules are then directed to a chamber 14 defined within an enclosure 20. The chamber maintains a heated, inert atmosphere with which to melt the semiconductor granules into a molten mass. A nozzle, 40, creates droplets from the molten mass, which then drop through a long drop tube 16. As the droplets move through the drop tube, they form spherical shaped semiconductor crystals 112. The drop tube is heated and the spherical shaped semiconductor crystals may be single crystals. An inductively coupled plasma torch positioned between the nozzle and the drop tube melts the droplets, but leaving a seed in-situ. The seed can thereby facilitate crystallization.
    Type: Grant
    Filed: December 10, 1998
    Date of Patent: June 13, 2000
    Assignee: Ball Semiconductor, Inc.
    Inventors: Murali Hanabe, Nainesh J. Patel, Evangellos Vekris
  • Patent number: 6051062
    Abstract: In producing an optical single crystal epitaxial film from a melt containing a transition metal on a single crystal substrate by a liquid phase epitaxial method, this process contains the steps of: annealing the film at a predetermined temperature in an ozonic atmosphere; and temperature-increasing and -decreasing to and from the predetermined temperature, wherein at least one of temperature-increasing and -decreasing steps, the film is exposed to a substantially ozone-free atmosphere.
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: April 18, 2000
    Assignee: NGK Insulators, Ltd.
    Inventors: Tatsuo Kawaguchi, Minoru Imaeda
  • Patent number: 6024793
    Abstract: For the purpose of separating a substance from a liquid mixture by crystallization, the inner walls of pipes in a crystallizer (S-1, S-2, S-3) are cooled by evaporating a liquid medium, the pressure of the gaseous phase of the medium being controlled in accordance with the temperature required for crystallization. In these conditions a layer of crystals forms on the outer walls of the pipes and can later be melted. The previously-formed crystal layer is melted in one crystallizer simultaneously with crystallization in another crystallizer. This is done by introducing gaseous medium which is produced in a crystallizer during the said evaporation. In addition, heat energy can be supplied to the crystallizer where melting occurs, in order to evaporate liquid medium there so that melting is accelerated. The two simultaneously operating crystallizers operate respectively as an evaporator and as a condenser in a refrigerating unit (11), thus saving considerable energy compared with known crystallization methods.
    Type: Grant
    Filed: June 4, 1997
    Date of Patent: February 15, 2000
    Assignee: Sulzer Chemtech AG
    Inventor: Rudolf Bischof
  • Patent number: 5985022
    Abstract: Optoelectric article includes a substrate made of an optoelectric single crystal and a film of a single crystal of lithium niobate formed on the substrate by a liquid phase epitaxial process, wherein a ratio of lithium/niobium of a composition of the film of the lithium niobate single crystal falls in a range of 48.6/51.4 to 49.5 to 50.5 or 50.5/49.5 to 52.3/47.7.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: November 16, 1999
    Assignee: NGK Insulators, Ltd.
    Inventors: Tsuguo Fukuda, Tatsuo Kawaguchi, Minoru Imaeda
  • Patent number: 5935534
    Abstract: In a crystallization method, a liquid mixture containing a crystallizable component is cooled so as to form and separate crystals of the crystallizable component. Then, a purified melt having purity substantially equal to that of the separated crystals, to which a polymerization inhibitor is added and which is heated to a temperature higher than a freezing point of the separated crystals, is circulated to flow contacting the crystals so as to accelerate melting. Then, the melted crystals are recovered along with the purified melt containing the polymerization inhibitor.
    Type: Grant
    Filed: December 2, 1996
    Date of Patent: August 10, 1999
    Assignees: JGC Corporation, Mitsubishi Chemical Corporation
    Inventors: Hiroshi Umino, Hiromitsu Shibuya, Nobuyasu Chikamatsu, Kazuo Kikuchi, Masahiko Yamagishi, Kiyoshi Takahashi
  • Patent number: 5795381
    Abstract: Methods for quantifying, in near real-time, the amount of silicon oxide (SiO) volatilized from a pool of molten silicon such as a Czochralski silicon melt and present in the atmosphere over the melt are disclosed. A preferred method includes reacting a gas sample containing SiO withdrawn from the atmosphere over the molten silicon with a reactant to form a detectable reaction product, determining the amount of reaction product formed, and correlating the determined amount of reaction product to the amount of SiO present in the atmosphere. The quantification of SiO is used for monitoring and/or controlling the amount of oxygen in the molten silicon or the oxygen content in single crystal silicon being drawn from the molten silicon. A SiO reaction probe and a system using the probe for monitoring and/or controlling oxygen are also disclosed.
    Type: Grant
    Filed: September 9, 1996
    Date of Patent: August 18, 1998
    Assignee: MEMC Electrical Materials, Inc.
    Inventor: John D. Holder
  • Patent number: 5746823
    Abstract: A method for forming an optical device includes the steps of providing a first plate having a first face defining a recess, filling the recess with a material which can be crystallized, and covering the first face and the recess with a second plate having a second face, so that the second face is in contact with the first face and the material in the recess is completely enclosed by the first and second plates. The material in the recess is thereby protected from chemical and mechanical damage, as well as evaporation. In addition, the plates can be transparent, allowing the material in the recess to be visually monitored. A grown crystalline film packed in the cell can be used as a non-liner and/or electro-optical device.
    Type: Grant
    Filed: September 8, 1995
    Date of Patent: May 5, 1998
    Assignee: University of Puerto Rico
    Inventor: Alexander Leyderman
  • Patent number: 5662740
    Abstract: In the manufacture of a single crystal film by epitaxial growth method, defects such as cracking are avoided by increasing the deviation of the lattice constant of the resulting film in the direction of growth from the substrate. Preferably, the deviation is increased at the rate of (0.4.about.9).times.10.sup.-4 %/.mu.m.
    Type: Grant
    Filed: October 17, 1994
    Date of Patent: September 2, 1997
    Assignee: TDK Corporation
    Inventors: Kazuhito Yamasawa, Atsushi Oido, Akio Nakata, Nobuya Uchida
  • Patent number: 5584929
    Abstract: A method of preparing a compound semiconductor crystal in a crucible involves first forming a boron or boron compound containing layer on an inner surface of the crucible and heat treating the same to form a B.sub.2 O.sub.3 containing layer. The resulting pretreated crucible is the employed for preparing the compound semiconductor crystal. By pretreating the crucible in this manner, it is possible to previously form a homogenous B.sub.2 O.sub.3 film on the crucible interior surface while preventing incomplete and heterogeneous coating of the B.sub.2 O.sub.3 film. Consequently, it is possible to prevent a raw material melt from wetting the crucible interior surface and thus to suppress polycrystallization, thereby preparing a compound semiconductor single crystal with an excellent yield.
    Type: Grant
    Filed: March 9, 1995
    Date of Patent: December 17, 1996
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Tomohiro Kawase
  • Patent number: 5476063
    Abstract: A seed crystal is connected with a polycrystal at one end of the polycrystal, the connected crystal material is melted under a zero-gravity or microgravity environment without any container, and a single crystal is grown.
    Type: Grant
    Filed: August 4, 1994
    Date of Patent: December 19, 1995
    Assignees: National Research Institute for Metals, National Space Development Agency of Japan
    Inventors: Isao Nakatani, Satoshi Takahashi, Isao Nishida, Kiyoshi Ozawa
  • Patent number: 5454344
    Abstract: A system for crystallization of polymers involving the use of a stationary housing with a rotor mounted for rotation within the housing. The rotor supports a plurality of spaced apart hollow discs and heated fluid is delivered to the interior of the discs. The polymer material to be treated is fed into the housing for heat exchange contact with the exterior surfaces of the discs. The rotation of the discs in addition serves as the propelling force for the material along the length of the housing at which point the material is discharged. The speed of rotation of the rotor is controlled to influence agitation and conveying of material in the housing to thereby control the crystallization reaction. A holdup mechanism which operates independently of the speed control is located adjacent the discharge location to contribute to the fixing of the residence time.
    Type: Grant
    Filed: November 16, 1994
    Date of Patent: October 3, 1995
    Assignee: Hosokawa Bepex Corporation
    Inventors: Ilya Pikus, Greg J. Kimball, Masayuki Inoue
  • Patent number: 5394827
    Abstract: A direct contact cryogenic crystallizer having a vertically oriented draft tube into which cryogenic fluid is injected at a high velocity along with warm gas and through which a crystal slurry is drawn for subsequent cooling and agitation for the production of crystals.
    Type: Grant
    Filed: July 15, 1994
    Date of Patent: March 7, 1995
    Assignee: Praxair Technology, Inc.
    Inventor: Alan T. Cheng
  • Patent number: 5362455
    Abstract: A direct contact cryogenic crystallizer having a vertically oriented draft tube into which cryogenic fluid is injected at a high velocity along with warm gas and through which a crystal slurry is drawn for subsequent cooling and agitation for the production of crystals.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: November 8, 1994
    Assignee: Praxair Technology, Inc.
    Inventor: Alan T. Cheng