Patents by Inventor Klaus Berger

Klaus Berger 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: 7498092
    Abstract: A perpendicular magnetic recording medium, such as a perpendicular magnetic recording disk, has a magnetic “torque” layer (MTL) that exerts a magnetic torque onto the perpendicular magnetic recording layer (RL) in the presence of the applied perpendicular write field. The MTL thus acts as a write assist layer in reversing the magnetization of the RL. A coupling layer (CL) is located between the MTL and the RL and provides the appropriate ferromagnetic coupling strength between the MTL and the RL.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: March 3, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Andreas Klaus Berger, Hoa Van Do
  • Publication number: 20080292907
    Abstract: A patterned perpendicular magnetic recording medium has discrete magnetic islands, each of which has a recording layer (RL) structure that comprises two exchange-coupled ferromagnetic layers. The RL structure may be an “exchange-spring” RL structure with an upper ferromagnetic layer (MAG2), sometimes called the exchange-spring layer (ESL), ferromagnetically coupled to a lower ferromagnetic layer (MAG1), sometimes called the media layer (ML). The RL structure may also include a coupling layer (CL) between MAG1 and MAG2 that permits ferromagnetic coupling. The interlayer exchange coupling between MAG1 and MAG2 may be optimized, in part, by adjusting the materials and thickness of the CL. The RL structure may also include a ferromagnetic lateral coupling layer (LCL) that is in contact with at least one of MAG1 and MAG2 for mediating intergranular exchange coupling in the ferromagnetic layer or layers with which it is in contact (MAG2 or MAG1).
    Type: Application
    Filed: May 22, 2007
    Publication date: November 27, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Andreas Klaus Berger, Eric E. Fullerton, Olav Hellwig, Byron Hassberg Lengsfield, III, Ernesto E. Marinero
  • Publication number: 20080261078
    Abstract: A perpendicular magnetic recording system and medium has a multilayered recording layer that includes an exchange-spring structure and a ferromagnetic lateral coupling layer (LCL). The exchange-spring structure is made up of two ferromagnetically exchange-coupled magnetic layers (MAG1 and MAG2), each with perpendicular magnetic anisotropy. MAG1 and MAG2 may have a coupling layer (CL) located between them that permits ferromagnetic exchange coupling of MAG1 with MAG2. The LCL is located either above or below MAG1 and in direct contact with MAG1 and mediates an effective intergranular exchange coupling in MAG1. The ferromagnetic alloy in the LCL has significantly greater intergranular exchange coupling than the ferromagnetic alloy in MAG1, which typically will include segregants such as oxides. The LCL is preferably free of oxides or other non-metallic segregants, which would tend to reduce intergranular exchange coupling in the LCL.
    Type: Application
    Filed: April 17, 2007
    Publication date: October 23, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B. V.
    Inventors: Andreas Klaus Berger, Eric E. Fullerton, Byron Hassberg Lengsfield, David Thomas Margulies
  • Publication number: 20080254324
    Abstract: A perpendicular magnetic recording medium has an “exchange-spring” type magnetic recording layer (RL) with an improved coupling layer (CL). The RL includes the first or lower ferromagnetic layer MAG1, sometimes called the “media” layer, the second or upper ferromagnetic layer MAG2, sometimes called the “exchange-spring” layer, and the intermediate CL that provides ferromagnetic exchange coupling between MAG1 and MAG2. The CL is formed of NiCr or RuCr based alloys, or CoCr or CoCrB alloys with high Cr and/or B content (Cr plus B>about 25 atomic percent), or RuCoCr alloys with low Co content (<about 65 atomic percent). For each CL composition there is a CL thickness range that provides the optimal interlayer exchange coupling between MAG1 and MAG2. The selected CL materials provide an exchange-type perpendicular magnetic recording medium with good magnetic performance, while the relatively high amount of Cr of the CL improves the corrosion resistance of the medium.
    Type: Application
    Filed: April 16, 2007
    Publication date: October 16, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHOLOGIES NETHERLANDS B.V.
    Inventors: Andreas Klaus Berger, Xiaoping Bian, Mary Frances Minardi, Kentaro Takano, Kai Tang
  • Publication number: 20080199735
    Abstract: A perpendicular magnetic recording system uses an exchange-spring type of perpendicular magnetic recording medium. The medium has a recording layer (RL) that includes a lower media layer (ML) and a multilayer exchange-spring layer (ESL) above the ML. The high anisotropy field (high-Hk) lower ML and the multilayer ESL are exchange-coupled across a coupling layer. The multilayer ESL has at least two ESLs separated by a coupling layer, with each of the ESLs having an Hk substantially less than the Hk of the ML. The exchange-spring structure with the multilayer ESL takes advantage of the fact that the write field magnitude and write field gradient vary as a function of distance from the write pole. The thicknesses and Hk values of each of the ESLs can be independently varied to optimize the overall recording performance of the medium.
    Type: Application
    Filed: February 18, 2007
    Publication date: August 21, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Andreas Klaus Berger, Eric E. Fullerton, Byron Hassberg Lengsfield
  • Publication number: 20080144213
    Abstract: A perpendicular magnetic recording layer (RL) structure has multiple granular ferromagnetic layers (MAGs) that are separated by ferromagnetic exchange-coupling layers (ECLs) as interlayers between the MAGS. The ECLs provide effective intergranular exchange-coupling in the MAGs. Each MAG is sufficiently thick to support independent recording states that are thermally stable, and does not rely on the overall RL thickness for thermal stability. Each ECL has significant intralayer coupling of its grains. The material of the ECL may be a CoCr alloy, such as a CoCrPtB alloy. The Cr and B in the ECL create sam11 segregation regions or sub-grains in the ECL that are exchange-coupled on a length-scale smaller than the grain size. For each MAG grain, there exist a multitude of magnetic states corresponding to different transition positions in the ECL.
    Type: Application
    Filed: December 15, 2006
    Publication date: June 19, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Andreas Klaus Berger, David Thomas Margulies, Natacha F. Supper
  • Publication number: 20080138662
    Abstract: A perpendicular magnetic recording medium has a multilayer recording layer (RL) structure that includes a ferromagnetic intergranular exchange enhancement layer for mediating intergranular exchange coupling in the other ferromagnetic layers in the RL structure. The RL structure may be a multilayer of a first ferromagnetic layer (MAG1) of granular polycrystalline Co alloy with Ta-oxide, a second ferromagnetic layer (MAG2) of granular polycrystalline Co alloy with Si-oxide, and an oxide-free CoCr capping layer on top of and in contact with MAG2 for mediating intergranular exchange coupling in MAG1 and MAG2. The RL structure may also be a multilayer of an intergranular exchange enhancement interlayer (IL) in between two ferromagnetic layers, MAG1 and MAG2, each with reduced or no intergranular exchange coupling. Because the IL is in direct contact with both MAG1 and MAG2, it directly mediates intergranular exchange coupling in each of MAG1 and MAG2.
    Type: Application
    Filed: December 7, 2006
    Publication date: June 12, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Andreas Klaus Berger, Qing Dai, Hoa Van Do, Yoshihiro Ikeda, David Thomas Margulies, Natacha F. Supper, Kentaro Takano, Min Xiao
  • Publication number: 20080070065
    Abstract: A perpendicular magnetic recording system and medium has a multilayered recording layer that includes an exchange-spring structure and a ferromagnetic lateral coupling layer (LCL). The exchange-spring structure is made up of two ferromagnetically exchange-coupled magnetic layers (MAG1 and MAG2), each with perpendicular magnetic anisotropy. MAG1 and MAG2 are either in direct contact with one another or have a coupling layer (CL) located between them. The LCL is located in direct contact with MAG2 and mediates intergranular exchange coupling in MAG2. The ferromagnetic alloy in the LCL has significantly greater intergranular exchange coupling than the ferromagnetic alloy in MAG2, which typically will include segregants such as oxides. The LCL is preferably free of oxides or other segregants, which would tend to reduce intergranular exchange coupling in the LCL.
    Type: Application
    Filed: September 14, 2006
    Publication date: March 20, 2008
    Applicant: HITACHI GLOBAL STORAGE TECHNOLOGIES NETHERLANDS B.V.
    Inventors: Andreas Klaus Berger, Hoa Van Do, Byron Hassberg Lengsfield, Natacha F. Supper
  • Publication number: 20080057349
    Abstract: A high performance perpendicular media with optimal exchange coupling between grains has improved thermal stability, writeability, and signal-to-noise ratio in a selected range of allowable intergranular exchange between the grains for high performing media. The writeability and byte error rate of a TaOx media are demonstrated to be substantially better than that of other designs.
    Type: Application
    Filed: September 6, 2006
    Publication date: March 6, 2008
    Inventors: Andreas Klaus Berger, Hoa Van Do, Yoshihiro Ikeda, Byron Hassberg Lengsfield, Hal Jervis Rosen, Kentaro Takano, Min Xiao
  • Publication number: 20070298285
    Abstract: A laminated magnetic recording structure for use in perpendicular or longitudinal recording is described. A small amount of ferromagnetic coupling is added between the two magnetic layers that are sufficiently decoupled to switch independently. In one embodiment the coupling is achieved by doping the spacer layer with a ferromagnetic material. Ruthenium (Ru), which is a preferred nonmagnetic material for spacer layers with cobalt (Co) being the preferred magnetic material. The weak ferromagnetic coupling can also be achieved through the use of platinum, palladium and alloys thereof for the spacer layer without the addition of a ferromagnetic element, but alternatively they can also be doped with ferromagnetic elements. For embodiments for perpendicular recording the spacer layer further can additionally comprise oxides of one or more elements selected from the group consisting of Si, Ta, Ti, Nb, Cr, V and B.
    Type: Application
    Filed: June 26, 2006
    Publication date: December 27, 2007
    Inventors: Andreas Klaus Berger, Hoa Van Do, Eric Edward Fullerton, David Thomas Margulies, Natacha Frederique Supper
  • Patent number: 7026401
    Abstract: The present invention relates to a process for producing a bimodal or multimodal mixture of amorphous polyolefins having a different molar mass, in which at least one amorphous polyolefin having a high molar mass is brought into contact and mixed with at least one amorphous polyolefin having a low molar mass in solution and the solvent is subsequently removed.
    Type: Grant
    Filed: June 21, 2000
    Date of Patent: April 11, 2006
    Assignee: Ticona GmbH
    Inventors: Frank Osan, Klaus Berger, Dieter Ruchatz, Oliver Stark, Toru Nakamura
  • Patent number: 6767966
    Abstract: The present invention describes a novel transparent polymer mixture with modified relaxation behavior and modified shrinkage behavior, comprising cycloolefin polymers. The polymer mixture comprises at least one amorphous polyolefin. The polymer mixture is used to produce mono- or biaxially oriented films, blister packs, or mixtures with other plastics, particularly with polyolefins. The polymer mixture is used in injection molding, injection blow molding or blow extrusion.
    Type: Grant
    Filed: October 31, 2002
    Date of Patent: July 27, 2004
    Assignee: Ticona GmbH
    Inventors: Klaus Berger, Wolfram Goerlitz, Wilfried Hatke
  • Patent number: 6762265
    Abstract: The invention relates to microstructured components comprising at least one cycloolefin copolymer, to a process for producing these microstructured components, and also to the use of these microstructured components.
    Type: Grant
    Filed: October 31, 2002
    Date of Patent: July 13, 2004
    Assignee: Ticona GmbH
    Inventors: Alexandra Jacobs-Hattwig, Klaus Berger, Dirk Sabbert, Jörg Landsiedel
  • Publication number: 20030166781
    Abstract: The present invention describes a novel transparent polymer mixture with modified relaxation behavior and modified shrinkage behavior, comprising cycloolefin polymers. The polymer mixture comprises at least one amorphous polyolefin. The polymer mixture is used to produce mono- or biaxially oriented films, blister packs, or mixtures with other plastics, particularly with polyolefins. The polymer mixture is used in injection molding, injection blow molding or blow extrusion.
    Type: Application
    Filed: October 31, 2002
    Publication date: September 4, 2003
    Inventors: Klaus Berger, Wolfram Goerlitz, Wilfried Hatke
  • Patent number: 6566475
    Abstract: The present invention relates to a polymer composition comprising one or more cycloolefin copolymers and one or more suitably formulated additives, having improved resistance to stress cracking in air or else in contact with media which give rise to stress cracking.
    Type: Grant
    Filed: May 3, 2001
    Date of Patent: May 20, 2003
    Assignee: Ticona GmbH
    Inventors: Alexandra Jacobs, Klaus Berger, Wilfried Hatke
  • Patent number: 6225407
    Abstract: The present invention relates to a polymer blend comprising one or more cycloolefin copolymers and one or more types of core-shell particles or one or more copolymers which are composed to some extent of rubbers with low glass transition temperatures, or a combination of one or more types of core-shell particles and of one or more copolymers which are composed to some extent of rubbers with low glass transition temperatures.
    Type: Grant
    Filed: June 16, 1999
    Date of Patent: May 1, 2001
    Assignee: Ticona GmbH
    Inventors: Alexandra Jacobs, Klaus Berger, Wilfried Hatke
  • Patent number: 5647238
    Abstract: To suppress the influence of roll eccentricities on a feedback control of a rolling-stock thickness in the thickness control, it is generally known to provide an insensitive dead zone for signal fluctuations caused by the roll eccentricities, and for the zone width of this insensitive dead zone to be varied relative to the magnitude of the signal fluctuations. To prevent actual thickness fluctuation in the rolling stock from leading to a widening of the dead zone, it is provided for the signal fluctuations drawn upon to vary the zone width (x) to be filtered by one or more band-pass filters (26, 27), whose mid-frequencies correspond to the fundamental frequency (.omega.) and, in some instances, to the first or further harmonic component frequencies (2.omega.) of the roll eccentricities (.DELTA.R).
    Type: Grant
    Filed: March 27, 1995
    Date of Patent: July 15, 1997
    Assignee: Siemens Aktiengesellschaft
    Inventors: Siegbert Steidl, Clemens Jungkunz, Klaus Berger
  • Patent number: 4534361
    Abstract: To improve the accuracy of blood pressure measurement by utilizing the Korotkoff noises, the frequency spectrum of the Korotkoff noises is analyzed, either by a plurality of filters (16, 17, 18; FIG. 1) or by a Fast Fourier Transform (FFT) system (54, 55; FIG. 2). If a plurality of filters are used (FIG. 1), which may be analog or digital, then the output amplitudes are rectified (19, 20, 21) and quotients are formed. If the quotients have a predetermined relationship, as determined by a discriminator (27, 28), a control logic provides output signals to a manometer (31) to indicate, respectively, systolic and diastolic blood pressure. For Fast Fourier Transform, a microprocessor can be used which, simultaneously, can provide clock sources to digitize output from the microphone coupled to the cuff of the blood pressure measuring instrument.
    Type: Grant
    Filed: October 29, 1982
    Date of Patent: August 13, 1985
    Assignee: Robert Bosch GmbH
    Inventors: Klaus Berger, Karl-Heinz Affeldt, Lutz Bottcher
  • Patent number: 4128844
    Abstract: Proceeding in order from the light-side to the beam-side of the target structure, the structure includes a transparent glass plate, a transparent signal electrode, a photoconductive layer of n-type CdSe, and a layer of n-type ZnSe. The interface between the two n-type layers is possessed of a multitude of interface states capable of capturing holes optically liberated in the photoconductor and electrons injected by the scanning beam. Beam-injected electrons cannot pass directly across the interface, and therefore dark current is reduced in a manner as effective as with p-n junction target structures. Each optically generated hole trapped at the interface lowers the potential barrier for beam-injected trapped electrons by an amount such as to cause more than one such electron to enter the conduction band of the CdSe layer, resulting in greater-than-unity amplification. Amplification by factors in excess of 100 can be achieved.
    Type: Grant
    Filed: September 26, 1977
    Date of Patent: December 5, 1978
    Assignee: Robert Bosch GmbH
    Inventors: Arno Illenberger, Gert Ruprecht, Klaus Berger