Patents by Inventor Alexei Gruverman

Alexei Gruverman 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).

  • Publication number: 20070274668
    Abstract: A method for switching the direction of polarization in a relatively small domain in a thin-film ferroelectric material whose direction of polarization is oriented normal to the surface of the material involves a step of moving an electrically-chargeable tip into contact with the surface of the ferroelectric material so that the direction of polarization in a region adjacent the tip becomes oriented in a preselected direction relative to the surface of the ferroelectric material. The tip is then pressed against the surface of the ferroelectric material so that the direction of polarization of the ferroelectric material within the area of the ferroelectric material in contact with the tip is reversed under the combined effect of the compressive influence of the tip and electric bias.
    Type: Application
    Filed: April 24, 2006
    Publication date: November 29, 2007
    Inventors: Sergei Kalinin, Arthur Baddorf, Ho Lee, Junsoo Shin, Alexei Gruverman, Edgar Karapetian, Mark Kachanov
  • Patent number: 7241656
    Abstract: A semiconductor device comprises a substrate, a ferroelectric capacitor which includes a ferroelectric film on the substrate, and a stress application layer which applies tensile or compressive stress to the ferroelectric film of the ferroelectric capacitor by applying stress to the substrate.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: July 10, 2007
    Assignee: Fujitsu Limited
    Inventors: Jeffrey Scott Cross, Mineharu Tsukada, Yoshimasa Horii, Alexei Gruverman, Angus Kingon
  • Patent number: 7239026
    Abstract: A semiconductor device comprises a substrate, a ferroelectric capacitor which includes a ferroelectric film on the substrate, and a stress application layer which applies tensile or compressive stress to the ferroelectric film of the ferroelectric capacitor by applying stress to the substrate.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: July 3, 2007
    Assignee: Fujitsu Limited
    Inventors: Jeffrey Scott Cross, Mineharu Tsukada, Yoshimasa Horii, Alexei Gruverman, Angus Kingon
  • Publication number: 20060273365
    Abstract: A semiconductor device comprises a substrate, a ferroelectric capacitor which includes a ferroelectric film on the substrate, and a stress application layer which applies tensile or compressive stress to the ferroelectric film of the ferroelectric capacitor by applying stress to the substrate.
    Type: Application
    Filed: May 25, 2006
    Publication date: December 7, 2006
    Applicant: FUJITSU LIMITED
    Inventors: Jeffrey Cross, Mineharu Tsukada, Yoshimasa Horii, Alexei Gruverman, Angus Kingon
  • Publication number: 20060211156
    Abstract: A semiconductor device comprises a substrate, a ferroelectric capacitor which includes a ferroelectric film on the substrate, and a stress application layer which applies tensile or compressive stress to the ferroelectric film of the ferroelectric capacitor by applying stress to the substrate.
    Type: Application
    Filed: May 25, 2006
    Publication date: September 21, 2006
    Applicant: FUJITSU LIMITED
    Inventors: Jeffrey Cross, Mineharu Tsukada, Yoshimasa Horii, Alexei Gruverman, Angus Kingon
  • Patent number: 7075135
    Abstract: A semiconductor device comprises a substrate, a ferroelectric capacitor which includes a ferroelectric film on the substrate, and a stress application layer which applies tensile or compressive stress to the ferroelectric film of the ferroelectric capacitor by applying stress to the substrate.
    Type: Grant
    Filed: November 20, 2003
    Date of Patent: July 11, 2006
    Assignee: Fujitsu Limited
    Inventors: Jeffrey Scott Cross, Mineharu Tsukada, Yoshimasa Horii, Alexei Gruverman, Angus Kingon
  • Publication number: 20040147047
    Abstract: A semiconductor device comprises a substrate, a ferroelectric capacitor which includes a ferroelectric film on the substrate, and a stress application layer which applies tensile or compressive stress to the ferroelectric film of the ferroelectric capacitor by applying stress to the substrate.
    Type: Application
    Filed: November 20, 2003
    Publication date: July 29, 2004
    Inventors: Jeffrey Scott Cross, Mineharu Tsukada, Yoshimasa Horii, Alexei Gruverman, Angus Kingon
  • Patent number: 6466039
    Abstract: A ferroelectric film measuring instrument and measuring method of the same which are able to measure the transient current during the polarization inversion of a ferroelectric capacitor having a small capacity with high precision. A pulse generator 10 generates a pulse signal and applies it through a transmission line and a tip 50 to an upper electrode 62 of a ferroelectric capacitor. The output current iFE from a lower electrode 64 at the time of application of the pulse is converted to a voltage Vo by a resistor 30. This is amplified by a preamplifier 40 and output. The current iFE is measured by the output voltage Vo.
    Type: Grant
    Filed: July 20, 2001
    Date of Patent: October 15, 2002
    Assignee: Sony Corporation
    Inventor: Alexei Gruverman
  • Publication number: 20020058343
    Abstract: A method is provided for evaluating a ferroelectric capacitor by examining a structure in a prescribed area on a surface of a ferroelectric membrane using a piezo-response mode of a scanning force microscope. The method adopts a layered structure, in which an electrode and the ferroelectric membrane form a pseudo ohmic contact, and comprises the steps of: inducing a localized polarization inversion in a selected crystal grain in the ferroelectric membrane by imposing a voltage pulse having a prescribed polarity; determining a retention time by obtaining a piezo-response image for a prescribed time till a complete inversion of a write domain; and determining a retention characteristic by measuring a time till a complete disappearance of a switched domain or by measuring a time-dependency at a region where the polarization inversion are being retained.
    Type: Application
    Filed: May 25, 2001
    Publication date: May 16, 2002
    Inventors: Alexei Gruverman, Masahiro Tanaka