Patents by Inventor Ralf Hammer
Ralf Hammer 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).
-
Patent number: 10987760Abstract: Method of manufacturing holding plate (11) including ceramic material of several chemical elements and configured for holding apparatus (10) for holding a component by electrostatic forces or vacuum, includes the steps of material removal from holding plate (11) by laser ablation, wherein by laser irradiation (1) protrusions (13) are formed on holding plate (11), end faces (13.1) of which span a carrier surface for the component, and surface modification of holding plate (11) by laser irradiation (1), wherein irradiation parameters of laser irradiation (1) are set such that at least one of the chemical elements of the ceramic material is enriched on the surface of holding plate (11). A method is also described of manufacturing holding apparatus (10) for holding a component by electrostatic forces or vacuum, holding plate (11) which is produced with the inventive method, and holding apparatus (10) with at least one holding plate (11).Type: GrantFiled: May 25, 2016Date of Patent: April 27, 2021Assignee: BERLINER GLAS KGAA HERBERT KUBATZ GMBH & CO.Inventors: Ralf Hammer, Stefan Hoescheler, Mike Fischer, Gregor Hasper
-
Patent number: 10475689Abstract: A method for processing a holding plate (10) of a clamping device (in particular clamp wafer chuck) for holding a component, in particular a wafer, wherein the holding plate (10) has a SiC-based surface (12) on which at least one protruding, SiC-based surface element (13) is formed, includes the steps of locally limited heating of the holding plate (10) in a predetermined surface section and creating the surface element (13) at the predetermined surface section by chemical vapor deposition, in particular by means of laser CVD. Applications of the method exist in repairing a holding plate (10) of a clamping device or manufacturing a holding plate (10) of a clamping device. Furthermore, a holding plate of a clamping device for holding a component, in particular a wafer, is described.Type: GrantFiled: January 17, 2018Date of Patent: November 12, 2019Assignee: Berliner Glas KGaA Herbert Kubatz GmbH & Co.Inventors: Volker Schmidt, Ralf Hammer, Gregor Hasper, Mike Fischer
-
Publication number: 20180211861Abstract: A method for processing a holding plate (10) of a clamping device (in particular clamp wafer chuck) for holding a component, in particular a wafer, wherein the holding plate (10) has a SiC-based surface (12) on which at least one protruding, SiC-based surface element (13) is formed, includes the steps of locally limited heating of the holding plate (10) in a predetermined surface section and creating the surface element (13) at the predetermined surface section by chemical vapor deposition, in particular by means of laser CVD. Applications of the method exist in repairing a holding plate (10) of a clamping device or manufacturing a holding plate (10) of a clamping device. Furthermore, a holding plate of a clamping device for holding a component, in particular a wafer, is described.Type: ApplicationFiled: January 17, 2018Publication date: July 26, 2018Inventors: Volker SCHMIDT, Ralf HAMMER, Gregor HASPER, Mike FISCHER
-
Publication number: 20160354864Abstract: Method of manufacturing holding plate (11) including ceramic material of several chemical elements and configured for holding apparatus (10) for holding a component by electrostatic forces or vacuum, includes the steps of material removal from holding plate (11) by laser ablation, wherein by laser irradiation (1) protrusions (13) are formed on holding plate (11), end faces (13.1) of which span a carrier surface for the component, and surface modification of holding plate (11) by laser irradiation (1), wherein irradiation parameters of laser irradiation (1) are set such that at least one of the chemical elements of the ceramic material is enriched on the surface of holding plate (11). A method is also described of manufacturing holding apparatus (10) for holding a component by electrostatic forces or vacuum, holding plate (11) which is produced with the inventive method, and holding apparatus (10) with at least one holding plate (11).Type: ApplicationFiled: May 25, 2016Publication date: December 8, 2016Inventors: Ralf HAMMER, Stefan HOESCHELER, Mike FISCHER, Gregor HASPER
-
Patent number: 8723288Abstract: A single crystal having a technologically generated cleavage surface that extends along a natural crystallographic cleavage plane with an accuracy of less than |0.001°| when measured over a length relevant for the technology of the single crystal or over each of a plurality of surface areas extending in the direction of separation and having a length ?2 mm within the technologically relevant surface area.Type: GrantFiled: September 7, 2011Date of Patent: May 13, 2014Assignee: Freiberger Compound Materials GmbHInventors: Ralf Hammer, Manfred Jurisch
-
Patent number: 8097080Abstract: A method of dividing single crystals, particularly of plates of parts thereof, is proposed, which can comprise: pre-adjusting the crystallographic cleavage plane (2?) relative to the cleavage device, setting a tensional intensity (K) by means of tensional fields (3?, 4?), determining an energy release rate G(?) in dependence from a possible deflection angle (?) from the cleavage plane (2?) upon crack propagation, controlling the tensional fields (3?, 4?) such that the crack further propagates in the single crystal, wherein G(0)?2?e(0) and simultaneously at least one of the following conditions is satisfied: ? ? G ? ? ? ? = 0 ? 2 ? ? e h ? ? if ? ? ? 2 ? G ? ? 2 ? 0 ? ? or ( 2.1 ) ? ? G ? ? ? ? 2 ? ? e h ? ? ? ? : ? ? 1 < ? < ? 2 . ( 2.Type: GrantFiled: November 14, 2008Date of Patent: January 17, 2012Assignee: Freiberger Compound Materials GmbHInventors: Ralf Hammer, Manfred Jurisch
-
Publication number: 20110318221Abstract: An embodiment of the invention provides a single crystal cleaved from a larger crystal and having a cleavage surface that extends along a natural crystallographic plane of the single crystal, the cleavage surface produced by generating a stress field to propagate a crack in the larger crystal along the natural plane, so that during cracking by the stress field a magnitude of a derivative of an energy release rate, G(?), generated by the stress field at a front of the crack as a function of angular deviation, ?, from the natural plane, is less than or equal to twice an effective step energy, ?e, divided by a step height, h.Type: ApplicationFiled: September 7, 2011Publication date: December 29, 2011Applicant: FREIBERGER COMPOUND MATERIALS GMBHInventors: Ralf Hammer, Manfred Jurisch
-
Patent number: 8061345Abstract: A method and a device for cutting a workpiece (1, 21) in a wire saw is described, wherein a workpiece (1, 21) is fixed in a wire saw by means of a mounting beam (2, 22). In the method according to the invention, the generation of a mark or a step on the cutting area along the cutting slit at the transition from the workpiece to the mounting beam (2, 22) is moved further to the edge of the cutting area or is avoided entirely. Therefore, the workpiece (1, 21) is held during the cutting operation in the wire saw by a mounting beam (2, 22) such that while one of the two piercing points (9; 29) lies on the surface of the workpiece (1, 21) and while simultaneously the other (10; 30) of the two piercing points (9, 10; 29, 30) lies on the surface of the mounting beam (2; 22), the piercing point lying on the surface of the workpiece is the entry side piercing point.Type: GrantFiled: February 1, 2006Date of Patent: November 22, 2011Assignee: Freiberger Compound Materials GmbHInventors: Ralf Hammer, Ralf Gruzsynsky
-
Publication number: 20090283761Abstract: A method of dividing single crystals, particularly of plates of parts thereof, is proposed, which can comprise: pre-adjusting the crystallographic cleavage plane (2?) relative to the cleavage device, setting a tensional intensity (K) by means of tensional fields (3?, 4?), determining an energy release rate G(?) in dependence from a possible deflection angle (?) from the cleavage plane (2?) upon crack propagation, controlling the tensional fields (3?, 4?) such that the crack further propagates in the single crystal, wherein G(0)?2?e(0) and simultaneously at least one of the following conditions is satisfied: ? ? G ? ? ? ? = 0 ? 2 ? ? e h ? ? if ? ? ? 2 ? G ? ? 2 ? 0 ? ? or ( 2.1 ) ? ? G ? ? ? ? 2 ? ? e h ? ? ? ? : ? ? 1 < ? < ? 2 , ( 2.Type: ApplicationFiled: November 14, 2008Publication date: November 19, 2009Inventors: Ralf HAMMER, Manfred Jurisch
-
Publication number: 20090064982Abstract: A method and a device for cutting a workpiece in a wire saw is described, wherein a workpiece is fixed in a wire saw by means of a mounting beam. In the method according to the invention, the generation of a mark or a step on the cutting area along the cutting slit at the transition from the workpiece to the mounting beam is moved further to the edge of the cutting area or is avoided entirely. Therefor, the workpiece is held during the cutting operation in the wire saw by a mounting beam such that while one of the two piercing points lies on the surface of the workpiece and while simultaneously the other of the two piercing points lies on the surface of the mounting beam, the piercing point lying on the surface of the workpiece is the entry side piercing point.Type: ApplicationFiled: November 12, 2008Publication date: March 12, 2009Inventors: Ralf Hammer, Ralf Gruzsynsky
-
Patent number: 7195542Abstract: A wire saw (1; 100) for cutting a workpiece includes a device (21, 22, 24, 27) for setting, controlling and/or maintaining a predetermined or desired water content in at least part of the gaseous medium that contacts the slurry. With the wire saw according to the invention and the process carried out using this wire saw, it is possible to achieve consistently good surface properties of the resulting wafers over a prolonged period of use of a slurry.Type: GrantFiled: July 12, 2006Date of Patent: March 27, 2007Assignee: Freiberger Compound Materials GmbHInventors: Ralf Hammer, André Kleinwechter, Sylvia Müller, Ralf Gruszynsky
-
Publication number: 20070049173Abstract: A wire saw (1; 100) for cutting a workpiece includes a device (21, 22, 24, 27) for setting, controlling and/or maintaining a predetermined or desired water content in at least part of the gaseous medium that contacts the slurry. With the wire saw according to the invention and the process carried out using this wire saw, it is possible to achieve consistently good surface properties of the resulting wafers over a prolonged period of use of a slurry.Type: ApplicationFiled: July 12, 2006Publication date: March 1, 2007Inventors: Ralf Hammer, Andre Kleinwechter, Sylvia Muller, Ralf Gruszynsky
-
Patent number: 7137865Abstract: A method for the division of single crystals, in particular of GaAs, is provided in which a single crystal (1) to be cut into at least two parts and a cutting tool (2, 3; 8, 8a, 8b, 8c) are moved relative to one another in a direction of advancement (V) and wherein the single crystal (1) is oriented in such a way that a specified crystallographic orientation (K) lies in the cutting plane (T), characterized in that an angle (?) between the specified crystallographic direction (K) and the direction of advancement (V) is chosen in such a way that forces which act on the cutting tool during cutting in a direction at right angles to the cutting plane compensate one another.Type: GrantFiled: July 30, 2001Date of Patent: November 21, 2006Assignee: Freiberger Compound Materials GmbHInventors: Ralf Hammer, André Kleinwechter, Tilo Flade, Cornelia Kumann, Ralf Gruszynsky
-
Publication number: 20060243265Abstract: A method and a device for cutting a workpiece (1, 21) in a wire saw is described, wherein a workpiece (1, 21) is fixed in a wire saw by means of a mounting beam (2, 22). In the method according to the invention, the generation of a mark or a step on the cutting area along the cutting slit at the transition from the workpiece to the mounting beam (2, 22) is moved further to the edge of the cutting area or is avoided entirely. Therfor, the workpiece (1, 21) is held during the cutting operation in the wire saw by a mounting beam (2, 22) such that while one of the two piercing points (9; 29) lies on the surface of the workpiece (1, 21) and while simultaneously the other (10; 30) of the two piercing points (9, 10; 29, 30) lies on the surface of the mounting beam (2; 22), the piercing point lying on the surface of the workpiece is the entry side piercing point.Type: ApplicationFiled: February 1, 2006Publication date: November 2, 2006Inventors: Ralf Hammer, Ralf Gruzsynsky
-
Patent number: 6923171Abstract: An apparatus and a method for determining the orientation of a crystallographic plane (100) relative to a crystal surface (2) are provided, in which the orientation is free from errors of adhesion of the crystal or contamination of the holders for the crystal. For this purpose, the angle which the crystal surface to be measured forms with a reference axis and the angle which the crystallographic plane forms with the reference axis are measured and subtracted. In a wire sawing apparatus with an X-Y positioning unit, next the desired correction is made with the aid of measurement of the orientation and at the same time the crystal is displaced in horizontal and vertical positions. As a result, there remains a further degree of freedom of rotation of the crystal in the cutting plane for achieving a cut which is free from forces perpendicular to the feed direction and wire direction, so that no tool deflection takes place or the cutting forces are minimal. Further, the precision of orientation is increased.Type: GrantFiled: June 11, 2002Date of Patent: August 2, 2005Assignee: Freiberger Compound Materials GmbHInventors: Ralf Hammer, Ralf Gruszynsky, André Kleinwechter, Tilo Flade
-
Publication number: 20040118338Abstract: A method for the division of single crystals, in particular of GaAs, is provided in which a single crystal (1) to be cut into at least two parts and a cutting tool (2, 3; 8, 8a, 8b, 8c) are moved relative to one another in a direction of advancement (V) and wherein the single crystal (1) is oriented in such a way that a specified crystallographic orientation (K) lies in the cutting plane (T), characterised in that an angle (&rgr;) between the specified crystallographic direction (K) and the direction of advancement (V) is chosen in such a way that forces which act on the cutting tool during cutting in a direction at right angles to the cutting plane compensate one another.Type: ApplicationFiled: April 18, 2003Publication date: June 24, 2004Inventors: Ralf Hammer, Andre Kleinwechter, Tilo Flade, Cornelia Kumann, Ralf Gruszynsky
-
Publication number: 20030005919Abstract: A method and a device for the division of materials, in particular of single crystals, in particular by inner hole cutting is provided, with a cutting disk (2) having a concentric hole whose edge (3) forms a cutting edge and wherein the cutting disk (2) is rotatable about its central axis in order to cut the single crystal (1), a positioning device for positioning the single crystal (1) to be cut relative to the cutting disk in such a way that the cutting disk moves in rotating manner through the single crystal in order to separate off a part (1a) of the single crystal (1), and a device for the supply of coolant-lubricant onto the cutting disk (2), wherein the device (10) for the supply of coolant-lubricant is arranged in such a way that viewed in the direction of rotation it supplies the coolant-lubricant on the exit side behind the passage of the cutting disk (2) through the single crystal (1), and a device for the supply of compressed air (12).Type: ApplicationFiled: July 8, 2002Publication date: January 9, 2003Inventors: Ralf Hammer, Ralf Gruszynsky, Andre Kleinwechter, Tilo Flade