Patents by Inventor Gundars RATNIEKS

Gundars RATNIEKS has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method for producing a single crystal from semiconductor material by the FZ method; device for carrying out the method and semiconductor silicon wafer
    Patent number: 11788201
    Abstract: Single crystals of semiconductor material are produced by an FZ method, wherein a molten zone is created between a feed rod and a growing single crystal; the method involving melting feed rod material in a high frequency magnetic field of a first induction coil; crystallizing material of the molten zone on top of the growing single crystal; rotating the growing single crystal about an axis of rotation and changing the direction of rotation and the speed of rotation according to a predetermined pattern; and imposing an alternating magnetic field of a second induction coil on the molten zone, wherein the alternating magnetic field is not axisymmetric with respect to the axis of rotation of the growing single crystal.
    Type: Grant
    Filed: June 4, 2019
    Date of Patent: October 17, 2023
    Assignee: Siltronic AG
    Inventors: Ludwig Altmannshofer, Goetz Meisterernst, Gundars Ratnieks, Simon Zitzelsberger
  • METHOD FOR PRODUCING A SINGLE CRYSTAL FROM SEMICONDUCTOR MATERIAL BY THE FZ METHOD; DEVICE FOR CARRYING OUT THE METHOD AND SEMICONDUCTOR SILICON WAFER
    Publication number: 20210222319
    Abstract: Single crystals of semiconductor material are produced by an FZ method, wherein a molten zone is created between a feed rod and a growing single crystal; the method involving melting feed rod material in a high frequency magnetic field of a first induction coil; crystallizing material of the molten zone on top of the growing single crystal; rotating the growing single crystal about an axis of rotation and changing the direction of rotation and the speed of rotation according to a predetermined pattern; and imposing an alternating magnetic field of a second induction coil on the molten zone, wherein the alternating magnetic field is not axisymmetric with respect to the axis of rotation of the growing single crystal.
    Type: Application
    Filed: June 4, 2019
    Publication date: July 22, 2021
    Applicant: SILTRONIC AG
    Inventors: Ludwig ALTMANNSHOFER, Goetz MEISTERERNST, Gundars RATNIEKS, Simon ZITZELSBERGER
  • Method for growing a single crystal by crystallizing the single crystal from a float zone
    Patent number: 9932691
    Abstract: A single crystal is grown in a float zone which is inductively heated and the crystallizing single crystal is rotated in a direction of rotation which is periodically reversed at intervals in accordance with an alternating plan, wherein a dwell time during which the single crystal is in a state of rest because of the reversal of the direction of rotation is limited to no more than 60 ms.
    Type: Grant
    Filed: November 19, 2015
    Date of Patent: April 3, 2018
    Assignee: SILTRONIC AG
    Inventors: Georg Raming, Ludwig Altmannshofer, Gundars Ratnieks, Martin Moeller, Frank Muemmler
  • Method and apparatus for producing a single crystal
    Patent number: 9422634
    Abstract: Single crystals are produced by means of the floating zone method, wherein the single crystal crystallizes below a melt zone at a crystallization boundary, and the emission of crystallization heat is impeded by a reflector surrounding the single crystal, wherein the single crystal is heated in the region of an outer edge of the crystallization boundary by means of a heating device in a first zone, wherein a distance ? between an outer triple point Ta at the outer edge of the crystallization boundary and a center Z of the crystallization boundary is influenced. An apparatus for producing the single crystal provides a heat source below the melting induction coil and above the reflector.
    Type: Grant
    Filed: December 5, 2012
    Date of Patent: August 23, 2016
    Assignee: SILTRONIC AG
    Inventors: Georg Raming, Ludwig Altmannshofer, Gundars Ratnieks, Johann Landrichinger, Josef Lobmeyer, Alfred Holzinger
  • Method For Growing A Single Crystal By Crystallizing The Single Crystal From A Float Zone
    Publication number: 20160177469
    Abstract: A single crystal is grown in a float zone which is inductively heated and the crystallizing single crystal is rotated in a direction of rotation which is periodically reversed at intervals in accordance with an alternating plan, wherein a dwell time during which the single crystal is in a state of rest because of the reversal of the direction of rotation is limited to no more than 60 ms.
    Type: Application
    Filed: November 19, 2015
    Publication date: June 23, 2016
    Inventors: Georg RAMING, Ludwig ALTMANNSHOFER, Gundars RATNIEKS, Martin MOELLER, Frank MUEMMLER