Patents Assigned to Siltronic AG
  • Method for polishing a substrate composed of semiconductor material
    Patent number: 8647985
    Abstract: Semiconductor material substrates are polished by a method including at least one polishing step A by means of which the substrate is polished on a polishing pad containing an abrasive material bonded in the polishing pad and a polishing agent solution is introduced between the substrate and the polishing pad during the polishing step; and at least one polishing step B by means of which the substrate is polished on a polishing pad containing an abrasive material-containing polishing pad and wherein a polishing agent slurry containing unbonded abrasive material is introduced between the substrate and the polishing pad during the polishing step.
    Type: Grant
    Filed: July 2, 2008
    Date of Patent: February 11, 2014
    Assignee: Siltronic AG
    Inventors: Juergen Schwandner, Thomas Buschhardt, Roland Koppert, Georg Pietsch
  • Method for polishing a semiconductor wafer
    Patent number: 8647173
    Abstract: A method of polishing a semiconductor wafer using a holding system including a lined cutout the size of the semiconductor wafer that is fixed to a carrier. The method includes holding the semiconductor wafer in the cutout through adhesion of a first side of the semiconductor wafer to a bearing surface in the cutout and polishing a second side of the held semiconductor wafer using a polishing pad that is fixed on a polishing plate while introducing a polishing agent between the second side of the semiconductor wafer and the polishing pad, the polishing pad including fixedly bonded abrasive materials. The carrier is guided during polishing such that a portion of the second side of the semiconductor wafer temporarily projects beyond a lateral edge of a surface of the polishing pad.
    Type: Grant
    Filed: March 11, 2013
    Date of Patent: February 11, 2014
    Assignee: Siltronic AG
    Inventors: Juergen Schwandner, Thomas Buschhardt, Roland Koppert
  • Method for producing semiconductor wafers composed of silicon with reduced pinholes
    Patent number: 8628613
    Abstract: Silicon semiconductor wafers are produced by pulling a single crystal at a seed crystal from a melt heated in a crucible; supplying heat to the center of the crucible bottom with a heating power which, in the course of the growth of a cylindrical section of the single crystal, is increased at least once to not less than 2 kW and is then decreased again; and slicing semiconductor wafers from the pulled single crystal.
    Type: Grant
    Filed: April 19, 2011
    Date of Patent: January 14, 2014
    Assignee: Siltronic AG
    Inventors: Martin Weber, Werner Schachinger, Piotr Filar
  • ULTRASONIC CLEANING METHOD AND ULTRASONIC CLEANING APPARATUS
    Publication number: 20130312786
    Abstract: An ultrasonic cleaning method for cleaning an object in a liquid in which a gas is dissolved includes preparing the liquid in which the gas is dissolved. The object is cleaned while applying ultrasonic waves to the liquid so that a ratio determined by dividing a vibration strength of the liquid at a fourth-order frequency of the ultrasonic waves by a vibration strength of the liquid at a fundamental frequency of the ultrasonic waves is larger than 0.8/1000.
    Type: Application
    Filed: May 13, 2013
    Publication date: November 28, 2013
    Applicant: Siltronic AG
    Inventors: Yoshihiro Mori, Masashi Uchibe, Teruo Haibara, Etsuko Kubo
  • ULTRASONIC CLEANING METHOD AND ULTRASONIC CLEANING APPARATUS
    Publication number: 20130312788
    Abstract: An ultrasonic cleaning method for cleaning an object in a liquid in which a first gas is dissolved includes preparing the liquid in which the first gas is dissolved and introducing a second gas into the liquid while irradiating the liquid with ultrasonic waves so as to realize a state where bubbles containing the first gas dissolved in the liquid continue to be generated. The object is cleaned in the state where the bubbles containing the first gas continue to be generated.
    Type: Application
    Filed: May 13, 2013
    Publication date: November 28, 2013
    Applicant: Siltronic AG
    Inventors: Etsuko Kubo, Teruo Haibara, Yoshihiro Mori, Masashi Uchibe
  • ULTRASONIC CLEANING METHOD AND ULTRASONIC CLEANING APPARATUS
    Publication number: 20130312785
    Abstract: An ultrasonic cleaning method for cleaning an object in a liquid in which a gas is dissolved includes preparing the liquid in which the gas is dissolved and stirring the liquid while irradiating the liquid with the ultrasonic waves so as to realize a state where bubbles containing the gas dissolved in the liquid continue to be generated. The object is cleaned in the state where the bubbles containing the gas continue to be generated.
    Type: Application
    Filed: May 10, 2013
    Publication date: November 28, 2013
    Applicant: Siltronic AG
    Inventors: Teruo Haibara, Etsuko Kubo, Yoshihiro Mori, Masashi Uchibe
  • ULTRASONIC CLEANING METHOD AND ULTRASONIC CLEANING APPARATUS
    Publication number: 20130312789
    Abstract: An ultrasonic cleaning method for cleaning an object in a liquid in which a gas is dissolved includes preparing the liquid in which the gas is dissolved and cleaning the object while irradiating the liquid with ultrasonic waves so that a region, where a spatial rate of change of a refractive index of the liquid in which the gas is dissolved is large relative to a case where ultrasonic waves are not applied, appears along a direction in which the ultrasonic waves travel.
    Type: Application
    Filed: May 13, 2013
    Publication date: November 28, 2013
    Applicant: Siltronic AG
    Inventors: Masashi Uchibe, Yoshihiro Mori, Teruo Haibara, Etsuko Kubo
  • Method for producing a single crystal of semiconductor material
    Patent number: 8580033
    Abstract: A single crystal of semiconductor material is produced by a method of melting semiconductor material granules by means of a first induction heating coil on a dish with a run-off tube consisting of the semiconductor material, forming a melt of molten granules which extends from the run-off tube in the form of a melt neck and a melt waist to a phase boundary, delivering heat to the melt by means of a second induction heating coil which has an opening through which the melt neck passes, crystallizing the melt at the phase boundary, and delivering a cooling gas to the run-off tube and to the melt neck in order to control the axial position of an interface between the run-off tube and the melt neck.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: November 12, 2013
    Assignee: Siltronic AG
    Inventors: Wilfried von Ammon, Ludwig Altmannshofer, Helge Riemann, Joerg Fischer
  • Method for the treatment of a semiconductor wafer
    Patent number: 8580046
    Abstract: Semiconductor wafers are treated in a liquid container filled at least partly with a solution containing hydrogen fluoride, such that surface oxide dissolves, are transported out of the solution along a transport direction and dried, and are then treated with an ozone-containing gas to oxidize the surface of the semiconductor wafer, wherein part of the semiconductor wafer surface comes into contact with the ozone-containing gas while another part of the surface is still in contact with the solution, and wherein the solution and the ozone-containing gas are spatially separated such that they do not come into contact with one another.
    Type: Grant
    Filed: November 13, 2012
    Date of Patent: November 12, 2013
    Assignee: Siltronic AG
    Inventors: Guenter Schwab, Diego Feijoo, Thomas Buschhardt, Hans-Joachim Luthe, Franz Sollinger
  • Cleaning apparatus, measurement method and calibration method
    Patent number: 8575571
    Abstract: A calibration method for calibrating a measurement device for measuring a concentration of a gas dissolved in a liquid includes varying the concentration of the gas dissolved in the liquid, and predetermining, as a reference concentration, a concentration of the gas at which an intensity of luminescence produced when the liquid is irradiated with ultrasonic waves shows a peak. The liquid is illuminated with ultrasonic waves while varying the concentration of the gas in the liquid and a measured value is measured, using the measurement device, as a concentration of the gas in the liquid when the intensity of the luminescence shows a peak. The measurement device is calibrated based on the measured value and the reference concentration.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: November 5, 2013
    Assignee: Siltronic AG
    Inventors: Teruo Haibara, Yoshihiro Mori, Etsuko Kubo, Masashi Uchibe
  • METHOD OF MANUFACTURING SILICON SINGLE CRYSTAL, SILICON SINGLE CRYSTAL, AND WAFER
    Publication number: 20130277809
    Abstract: P-type silicon single crystals from which wafers having high resistivity, good radial uniformity of resistivity and less variation in resistivity can be obtained, are manufactured by the Czochralski method from an initial silicon melt in which boron and phosphorus are present, the boron concentration is not higher than 4E14 atoms/cm3 and the ratio of the phosphorus concentration to the boron concentration is not lower than 0.42 and not higher than 0.50.
    Type: Application
    Filed: November 10, 2011
    Publication date: October 24, 2013
    Applicant: SILTRONIC AG
    Inventors: Katsuhiko Nakai, Masamichi Ohkubo
  • METHOD OF MANUFACTURING ANNEALED WAFER
    Publication number: 20130273719
    Abstract: Annealed wafers having reduced residual voids after annealing and reduced deterioration of TDDB characteristics of an oxide film formed on the annealed wafer, while extending the range of nitrogen concentration contained in a silicon single crystal, are prepared by a method wherein crystal pulling conditions are controlled such that a ratio V/G between a crystal pulling rate V and an average axial temperature gradient G is ?0.9×(V/G)crit and ?2.5×(V/G)crit, and hydrogen partial pressure is ?3 Pa and ?40 Pa. The silicon single crystal has a nitrogen concentration of >5×1014 atoms/cm3 and ?6×1015 atoms/cm3, a carbon concentration of ?1×1015 atoms/cm3 and ?9×1015 atoms/cm3, and heat treatment is performed in a noble gas atmosphere having an impurity concentration of ?5 ppma, or in a non-oxidizing atmosphere.
    Type: Application
    Filed: December 5, 2011
    Publication date: October 17, 2013
    Applicant: SILTRONIC AG
    Inventors: Katsuhiko Nakai, Masamichi Ohkubo
  • DISSOLVED NITROGEN CONCENTRATION MONITORING METHOD, SUBSTRATE CLEANING METHOD, AND SUBSTRATE CLEANING APPARATUS
    Publication number: 20130263887
    Abstract: A dissolved nitrogen concentration monitoring method is used for monitoring a dissolved nitrogen concentration of a cleaning liquid when an ultrasonic wave is irradiated onto the cleaning liquid in which a substrate is dipped. The method includes measuring an amount of increase of a dissolved oxygen concentration of the cleaning liquid resulting from an oxygen molecule generated from a water molecule as a result of a radical reaction caused by ultrasonic wave irradiation. A dissolved nitrogen concentration of the cleaning liquid is calculated from the measured amount of increase of dissolved oxygen concentration based on a predetermined relationship between a dissolved nitrogen concentration and an amount of increase of dissolved oxygen concentration.
    Type: Application
    Filed: December 13, 2011
    Publication date: October 10, 2013
    Applicant: SILTRONIC AG
    Inventors: Teruo Haibara, Etsuko Kubo, Yoshihiro Mori, Masashi Uchibe
  • Method for producing an epitaxially coated semiconductor wafer
    Patent number: 8551870
    Abstract: Epitaxially coated semiconductor wafers are produced by minimally the following steps in the order specified: (a) depositing an epitaxial layer on one side of a semiconductor wafer; (b) first polishing the epitaxially coated side of the semiconductor wafer with a polishing pad with fixed abrasive while supplying a polishing solution which is free of solids; (c) CMP polishing of the epitaxially coated side of the semiconductor wafer with a soft polishing pad which contains no fixed abrasive, while supplying a polishing agent suspension; (d) depositing another epitaxial layer on the previously epitaxially coated and polished side of the semiconductor wafer.
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: October 8, 2013
    Assignee: Siltronic AG
    Inventors: Juergen Schwandner, Roland Koppert
  • Annealed wafer and manufacturing method of annealed wafer
    Patent number: 8545622
    Abstract: An annealed wafer in which oxygen precipitation is uniform in the substrate plane and a manufacturing method thereof are provided. A nitrogen-doped silicon single crystal substrate pulled at the cooling rate of 4° C./minute or more during crystal growth between 1100 and 1000° C. wherein the nitrogen concentration is 1×1014 to 5×1015 atoms/cm3 and V/G satisfies predetermined conditions serves as a substrate, and the substrate is subjected to heat treatment in a non-oxidative atmosphere.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: October 1, 2013
    Assignee: Siltronic AG
    Inventors: Katsuhiko Nakai, Koji Fukuhara
  • Method for producing a semiconductor wafer
    Patent number: 8529315
    Abstract: A method of producing a semiconductor wafer includes a plurality of steps carried out in the following order. Simultaneous double-side material-removal processing is carried out on a semiconductor wafer sliced from a single crystal by processing the semiconductor wafer between two rotating ring-shaped working disks. Each working disk includes first abrasives having an average grain size in a range of 5.0 to 20.0 ?m. Both sides of the semiconductor wafer are treated with an alkaline medium. Grinding of the front and rear sides of the semiconductor wafer is carried out. For the grinding of each side a first side is held using a wafer holder and the other side is processed using a grinding tool. The grinding tool includes second abrasives having an average grain size that is smaller than the average grain size of the first abrasives and having an average grain size being in a range of 1.0 to 10.0 ?m.
    Type: Grant
    Filed: January 20, 2011
    Date of Patent: September 10, 2013
    Assignee: Siltronic AG
    Inventors: Juergen Schwandner, Michael Kerstan
  • Silicon wafer and method for producing the same
    Patent number: 8524001
    Abstract: Silicon wafers having excellent voltage resistance characteristics of an oxide film and high C-mode characteristics are derived from single crystal silicon ingots doped with nitrogen and hydrogen, characterized in that a plurality of voids constituting a bubble-like void aggregates are present ?50% relative to total voids; a V1 region having a void density of over 2×104/cm3 and below 1×105/cm3 is ?20% of the total area of wafer; a V2 region having a void density of 5×102 to 2×104/cm3 occupies ?80% of the total area of the wafer; and bulk microdefect density is ?5×108/cm3.
    Type: Grant
    Filed: December 16, 2009
    Date of Patent: September 3, 2013
    Assignee: Siltronic AG
    Inventors: Katsuhiko Nakai, Atsushi Ikari, Masamichi Ohkubo
  • Silicon wafer and method for producing the same
    Patent number: 8524002
    Abstract: Silicon wafers doped with nitrogen, hydrogen and carbon, have a plurality of voids, wherein 50% or more of the total number of voids are bubble-like shaped aggregates of voids; a V1 region having a void density of over 2×104/cm3 and below 1×105/cm3 which occupies 20% or less of the total area of the silicon wafer; a V2 region having a void density of 5×102 to 2×104/cm3 which occupies 80% or more of the total area of said silicon wafer; and a bulk micro defect density which is 5×108/cm3 or more, have excellent GOI characteristics and a high C-mode pass rate. The wafers are cut from a single crystal pulled by a method in which carbon, nitrogen, and hydrogen dopants are controlled, and the crystal is subjected to rapid cooling.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: September 3, 2013
    Assignee: Siltronic AG
    Inventors: Katsuhiko Nakai, Masamichi Ohkubo
  • METHOD AND AN APPARATUS FOR GROWING A SILICON SINGLE CRYSTAL FROM A MELT
    Publication number: 20130220216
    Abstract: Silicon single crystals are grown from the melt by providing the melt in a crucible; imposing a horizontal magnetic field on the melt; directing a gas between the single crystal and a heat shield to a melt free surface, and controlling the gas to flow over a region of the melt free surface extending in a direction substantially perpendicular to the magnetic induction. A suitable apparatus has a crucible for holding the melt; a heat shield surrounding the silicon single crystal having a lower end which is connected to a bottom cover facing a melt free surface and a non-axisymmetric shape with respect to a crucible axis, such that gas which is directed between the crystal and the heat shield to the melt free surface is forced to flow over a region of the melt which extends substantially perpendicular to the magnetic induction.
    Type: Application
    Filed: April 8, 2013
    Publication date: August 29, 2013
    Applicant: Siltronic AG
    Inventor: Siltronic AG
  • Method for the simultaneous double-sided material removal processing of a plurality of semiconductor wafers
    Patent number: 8512099
    Abstract: A device for double-sided processing of flat workpieces has upper and lower working discs forming between them a working gap containing a carrier disc with cutout(s) for workpiece(s), the carrier disc having circumferential teeth by means of which it rolls on an inner and an outer gear wheel or pin ring, wherein the gear wheels or pin rings have a multiplicity of gear or pin arrangements which engage the teeth of the carrier discs during rolling, at least one of the pin arrangements having a guide which delimits movement of the margin of the carrier disc in at least one axial direction, the guide formed by a circumferential shoulder or a circumferential groove.
    Type: Grant
    Filed: October 19, 2009
    Date of Patent: August 20, 2013
    Assignees: Siltronic AG, Peter Wolters GmbH
    Inventors: Michael Kerstan, Georg Pietsch, Frank Runkel, Conrad von Bechtolsheim, Helge Moeller