Patents by Inventor Tsann Linn

Tsann Linn 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: 20050009211
    Abstract: A tunneling magnetoresistive (TMR) sensor includes a first ferromagnetic (FM) layer (e.g. a sense or reference layer), a barrier layer formed over the first FM layer, and a second FM layer (e.g. a sense or reference layer) formed over the barrier layer. The barrier layer is made of magnesium-oxide (Mg—O). The sense and reference layers of the TMR sensor exhibit controlled magnetic properties, the barrier layer provides a low junction resistance-area product, and the TMR sensor exhibits a high TMR coefficient. The junction resistance is sufficiently low so as to prevent electrostatic discharge (ESD) damage to submicron-sized TMR sensors used for magnetic recording at ultrahigh densities.
    Type: Application
    Filed: July 28, 2004
    Publication date: January 13, 2005
    Inventors: Tsann Linn, Daniele Mauri
  • Patent number: 6841395
    Abstract: A fabrication process for a tunneling magnetoresistance (TMR) sensor is disclosed. In particular, a unique method of forming a barrier layer of the TMR sensor is utilized so that the TMR sensor exhibits good magnetic and TMR properties. In one particular example, the barrier layer is formed by depositing a metallic film in an argon gas in a DC magnetron sputtering module, depositing an oxygen-doped metallic film in mixed xenon and oxygen gases in an ion-beam sputtering module, and oxidizing these films in an oxygen gas in an oxygen treatment module. This three-step barrier layer formation process minimizes oxygen penetration into ferromagnetic (FM) sense and pinned layers of the TMR sensor and optimally controls oxygen doping into the barrier layer. As a result, the FM sense and pinned layers exhibit controlled magnetic properties, the barrier layer provides a low junction resistance-area product, and the TMR sensor exhibits a high TMR coefficient.
    Type: Grant
    Filed: November 25, 2002
    Date of Patent: January 11, 2005
    Assignee: International Business Machines Corporation
    Inventors: Tsann Linn, Daniele Mauri
  • Publication number: 20040101978
    Abstract: A fabrication process for a tunneling magnetoresistance (TMR) sensor is disclosed. In particular, a unique method of forming a barrier layer of the TMR sensor is utilized so that the TMR sensor exhibits good magnetic and TMR properties. In one particular example, the barrier layer is formed by depositing a metallic film in an argon gas in a DC magnetron sputtering module, depositing an oxygen-doped metallic film in mixed xenon and oxygen gases in an ion-beam sputtering module, and oxidizing these films in an oxygen gas in an oxygen treatment module. This three-step barrier layer formation process minimizes oxygen penetration into ferromagnetic (FM) sense and pinned layers of the TMR sensor and optimally controls oxygen doping into the barrier layer. As a result, the FM sense and pinned layers exhibit controlled magnetic properties, the barrier layer provides a low junction resistance-area product, and the TMR sensor exhibits a high TMR coefficient.
    Type: Application
    Filed: November 25, 2002
    Publication date: May 27, 2004
    Inventors: Tsann Linn, Daniele Mauri
  • Patent number: 6114719
    Abstract: A magnetic tunnel junction (MTJ) memory cell uses a biasing ferromagnetic layer in the MTJ stack of layers that is magnetostatically coupled with the free ferromagnetic layer in the MTJ stack to provide transverse and/or longitudinal bias fields to the free ferromagnetic layer. The MTJ is formed on an electrical lead on a substrate and is made up of a stack of layers.
    Type: Grant
    Filed: May 29, 1998
    Date of Patent: September 5, 2000
    Assignee: International Business Machines Corporation
    Inventors: Frederick Hayes Dill, Robert Edward Fontana, Jr., Tsann Linn, Stuart Stephen Papworth Parkin, Ching Hwa Tsang