Patents by Inventor Theodore Zhu

Theodore Zhu 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: 7200035
    Abstract: A magneto-resistive memory comprising magneto-resistive memory cells is disclosed, comprising two pinned magnetic layers on one side of a free magnetic layer. The pinned magnetic layers are formed with anti-parallel magnetization orientations such that a net magnetic moment of the two layers is substantially zero. The influence of pinned magnetic layers on free magnetic layer magnetization orientations is substantially eliminated, allowing for increased predictability in switching behavior and increased write selectivity of memory cells.
    Type: Grant
    Filed: June 6, 2005
    Date of Patent: April 3, 2007
    Assignee: Micron Technology, Inc.
    Inventors: Theodore Zhu, Yong Lu, Anthony Arrott
  • Patent number: 7166479
    Abstract: A monolithically formed ferromagnetic thin-film memory is disclosed that has local shielding on at least two sides of selected magnetic storage elements. The local shielding preferably extends along the back and side surfaces of a word line and/or digital lines of a conventional magnetic memory. In this configuration, the local shielding not only may help reduce externally generated EMI, internally generated cross-talk and other unwanted fields in the magnetic bit region, but may also help enhance the desired magnetic fields in the bit region.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: January 23, 2007
    Assignee: Micron Technology, Inc.
    Inventors: Theodore Zhu, Jeffrey S. Sather
  • Patent number: 7038940
    Abstract: A magneto-resistive memory that has a shared word line and sense line is disclosed. By providing the shared word line and sense line, the number of relatively large drivers required to drive the word line and sense line currents can be reduced. This reduces the peripheral overhead of the memory, and may increase the overall density and reduce the overall power of the memory.
    Type: Grant
    Filed: January 7, 2005
    Date of Patent: May 2, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Richard W. Swanson, William J. Johnson, Theodore Zhu, Anthony S. Arrott
  • Publication number: 20060083088
    Abstract: The semiconductor industry seeks to replace traditional volatile memory devices with improved non-volatile memory devices. The increased demand for a significantly advanced, efficient, and non-volatile data retention technique has driven the development of integrated Giant-Magneto-resistive (GMR) structures. The present teachings relates to integrated latch memory and logic devices and, in particular, concerns a spin dependent logic device that may be integrated with conventional semiconductor-based logic devices to construct high-speed non-volatile static random access memory (SRAM) cells.
    Type: Application
    Filed: June 6, 2005
    Publication date: April 20, 2006
    Inventors: Romney Katti, Theodore Zhu
  • Patent number: 7029923
    Abstract: A magnetic bit structure for a magneto-resistive memory is disclosed that has bit ends that are sufficiently large to accommodate a minimum size contact or via hole. By providing such an arrangement, the magnetic bit structure may be fabricated using conventional contact and/or via processing steps. As such, the cost of manufacturing the device may be reduced, and the overall achievable yield may be increased.
    Type: Grant
    Filed: December 11, 2003
    Date of Patent: April 18, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Harry Liu, William Larson, Lonny Berg, Theodore Zhu, Shaoping Li, Romney R. Katti, Yong Lu, Anthony Arrott
  • Publication number: 20060063278
    Abstract: A monolithically formed ferromagnetic thin-film memory is disclosed that has local shielding on at least two sides of selected magnetic storage elements. The local shielding preferably extends along the back and side surfaces of a word line and/or digital lines of a conventional magnetic memory. In this configuration, the local shielding not only may help reduce externally generated EMI, internally generated cross-talk and other unwanted fields in the magnetic bit region, but may also help enhance the desired magnetic fields in the bit region.
    Type: Application
    Filed: November 19, 2004
    Publication date: March 23, 2006
    Applicant: Micron Technology, Inc.
    Inventors: Theodore Zhu, Jeffrey Sather
  • Patent number: 6992918
    Abstract: MRAM architectures are disclosed that produce an increased write margin and write selectivity without significantly reducing the packing density of the memory. The major axes of the magneto-resistive bits are offset relative to the axes of the digital lines to produce a magnetic field component from the digital line current that extends along the major axis of the magneto-resistive bits.
    Type: Grant
    Filed: July 7, 2003
    Date of Patent: January 31, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Shaoping Li, Theodore Zhu, Anthony S. Arrott, Harry Liu, William L. Larson, Yong Lu
  • Patent number: 6968482
    Abstract: A redundancy scheme for a memory is disclosed that is programmable both before and after the memory device is packaged and/or installed in a system. This is preferably accomplished by using programmable non-volatile memory elements to control the replacement circuitry. Because the programmable memory elements are non-volatile, the desired replacement configuration is not lost during shipping, or if power is lost in a system. By allowing post-packaging replacement of defective memory elements, the overall yield of the device may be improved. By allowing post system installation replacement of defective memory elements, the reliability of many systems may be improved. In addition, the disclosed redundancy scheme allows two or more defective memory elements from different rows or columns to be replaced with memory elements from a single redundant low or column. This provides added flexibility during the replacement process.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: November 22, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Theodore Zhu, Gary Kirchner, Richard W. Swanson, Yong Lu
  • Publication number: 20050226039
    Abstract: A magneto-resistive memory comprising magneto-resistive memory cells is disclosed, comprising two pinned magnetic layers on one side of a free magnetic layer. The pinned magnetic layers are formed with anti-parallel magnetization orientations such that a net magnetic moment of the two layers is substantially zero. The influence of pinned magnetic layers on free magnetic layer magnetization orientations is substantially eliminated, allowing for increased predictability in switching behavior and increased write selectivity of memory cells.
    Type: Application
    Filed: June 6, 2005
    Publication date: October 13, 2005
    Inventors: Theodore Zhu, Yong Lu, Anthony Arrott
  • Publication number: 20050226040
    Abstract: A magneto-resistive memory comprising magneto-resistive memory cells is disclosed, comprising a pinned magnetic layer and a free magnetic layer. The two magnetic layers are formed having widened regions at the ends of the layers. As such, the shape made out by the magneto-resisitve memory, from a top-view perspective, is wide at the ends and narrower at the mid-, forming an I shape in one preferred embodiment. The end portions of the free magnetic layer are allowed to magnetically couple to the end portions of the pinned magnetic layer such that magnetic coupling is shifted to these widened regions and coupling in the mid-portion between the widened regions is minimized. Thus, the influence of the pinned magnetic layer on the magnetization orientation of the mid-portion of the free magnetic layer is substantially eliminated, allowing for increased predictability in switching behavior and increased write selectivity of memory cells.
    Type: Application
    Filed: June 7, 2005
    Publication date: October 13, 2005
    Inventors: Theodore Zhu, Yong Lu, Anthony Arrott, Joel Drewes
  • Publication number: 20050185452
    Abstract: A magneto-resistive memory that has a shared word line and sense line is disclosed. By providing the shared word line and sense line, the number of relatively large drivers required to drive the word line and sense line currents can be reduced. This reduces the peripheral overhead of the memory, and may increase the overall density and reduce the overall power of the memory.
    Type: Application
    Filed: January 7, 2005
    Publication date: August 25, 2005
    Inventors: Richard Swanson, William Johnson, Theodore Zhu, Anthony Arrott
  • Patent number: 6920064
    Abstract: A magneto-resistive memory comprises magneto-resistive memory cells comprising two pinned magnetic layers on one side of a free magnetic layer. The pinned magnetic layers are formed with anti-parallel magnetization orientations such that a net magnetic moment of the two layers is substantially zero. The influence of pinned magnetic layers on free magnetic layer magnetization orientations is substantially eliminated, allowing for increased predictability in switching behavior and increased write selectivity of memory cells.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: July 19, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Theodore Zhu, Yong Lu, Anthony Arrott
  • Publication number: 20050141304
    Abstract: A redundancy scheme for a memory is disclosed that is programmable both before and after the memory device is packaged and/or installed in a system. This is preferably accomplished by using programmable non-volatile memory elements to control the replacement circuitry. Because the programmable memory elements are non-volatile, the desired replacement configuration is not lost during shipping, or if power is lost in a system. By allowing post-packaging replacement of defective memory elements, the overall yield of the device may be improved. By allowing post system installation replacement of defective memory elements, the reliability of many systems may be improved. In addition, the disclosed redundancy scheme allows two or more defective memory elements from different rows or columns to be replaced with memory elements from a single redundant low or column. This provides added flexibility during the replacement process.
    Type: Application
    Filed: February 25, 2005
    Publication date: June 30, 2005
    Inventors: Theodore Zhu, Gary Kirchner, Richard Swanson, Young Lu
  • Publication number: 20050141303
    Abstract: A redundancy scheme for a memory is disclosed that is programmable both before and after the memory device is packaged and/or installed in a system. This is preferably accomplished by using programmable non-volatile memory elements to control the replacement circuitry. Because the programmable memory elements are non-volatile, the desired replacement configuration is not lost during shipping, or if power is lost in a system. By allowing post-packaging replacement of defective memory elements, the overall yield of the device may be improved. By allowing post system installation replacement of defective memory elements, the reliability of many systems may be improved. In addition, the disclosed redundancy scheme allows two or more defective memory elements from different rows or columns to be replaced with memory elements from a single redundant low or column. This provides added flexibility during the replacement process.
    Type: Application
    Filed: February 25, 2005
    Publication date: June 30, 2005
    Inventors: Theodore Zhu, Gary Kirchner, Richard Swanson, Yong Lu
  • Publication number: 20050141305
    Abstract: A redundancy scheme for a memory is disclosed that is programmable both before and after the memory device is packaged and/or installed in a system. This is preferably accomplished by using programmable non-volatile memory elements to control the replacement circuitry. Because the programmable memory elements are non-volatile, the desired replacement configuration is not lost during shipping, or if power is lost in a system. By allowing post-packaging replacement of defective memory elements, the overall yield of the device may be improved. By allowing post system installation replacement of defective memory elements, the reliability of many systems may be improved. In addition, the disclosed redundancy scheme allows two or more defective memory elements from different rows or columns to be replaced with memory elements from a single redundant low or column. This provides added flexibility during the replacement process.
    Type: Application
    Filed: February 25, 2005
    Publication date: June 30, 2005
    Inventors: Theodore Zhu, Gary Kirchner, Richard Swanson, Young Lu
  • Patent number: 6906950
    Abstract: A magneto-resistive memory comprising magneto-resistive memory cells is disclosed, comprising a pinned magnetic layer and a free magnetic layer. The two magnetic layers are formed having widened regions at the ends of the layers. As such, the shape made out by the magneto-resisitve memory, from a top-view perspective, is wide at the ends and narrower at the mid-, forming an I shape in one preferred embodiment. The end portions of the free magnetic layer are allowed to magnetically couple to the end portions of the pinned magnetic layer such that magnetic coupling is shifted to these widened regions and coupling in the mid-portion between the widened regions is minimized. Thus, the influence of the pinned magnetic layer on the magnetization orientation of the mid-portion of the free magnetic layer is substantially eliminated, allowing for increased predictability in switching behavior and increased write selectivity of memory cells.
    Type: Grant
    Filed: July 7, 2004
    Date of Patent: June 14, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Theodore Zhu, Yong Lu, Anthony Arrott, Joel Drewes
  • Patent number: 6887719
    Abstract: A process that advantageously forms MRAM cells without the application of ion beam milling processes. Unlike conventional processes that rely on ion beam milling processes to remove materials from a magnetoresistive sandwich from areas other than areas that will later form MRAM cell bodies, this process forms a layer of photoresist over areas other than those areas that correspond to MRAM cell bodies. The photoresist is lifted off after the deposition of a magnetoresistive sandwich that forms the MRAM cell bodies, thereby safely removing the magnetoresistive sandwich from undesired areas while maintaining the magnetoresistive sandwich in the areas corresponding to MRAM cell bodies.
    Type: Grant
    Filed: October 2, 2003
    Date of Patent: May 3, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Yong Lu, Theodore Zhu
  • Patent number: 6872993
    Abstract: A monolithically formed ferromagnetic thin-film memory is disclosed that has local shielding on at least two sides of selected magnetic storage elements. The local shielding preferably extends along the back and side surfaces of a word line and/or digital lines of a conventional magnetic memory. In this configuration, the local shielding not only may help reduce externally generated EMI, internally generated cross-talk and other unwanted fields in the magnetic bit region, but may also help enhance the desired magnetic fields in the bit region.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: March 29, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Theodore Zhu, Jeffrey S. Sather
  • Patent number: 6872997
    Abstract: A magnetic bit structure for a magneto-resistive memory is disclosed that has bit ends that are sufficiently large to accommodate a minimum size contact or via hole. By providing such an arrangement, the magnetic bit structure may be fabricated using conventional contact and/or via processing steps. As such, the cost of manufacturing the device may be reduced, and the overall achievable yield may be increased.
    Type: Grant
    Filed: January 26, 2004
    Date of Patent: March 29, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Harry Liu, William Larson, Lonny Berg, Theodore Zhu, Shaoping Li, Romney R. Katti, Yong Lu, Anthony Arrott
  • Patent number: 6862700
    Abstract: A redundancy scheme for a memory is disclosed that is programmable both before and after the memory device is packaged and/or installed in a system. This is preferably accomplished by using programmable non-volatile memory elements to control the replacement circuitry. Because the programmable memory elements are non-volatile, the desired replacement configuration is not lost during shipping, or if power is lost in a system. By allowing post-packaging replacement of defective memory elements, the overall yield of the device may be improved. By allowing post system installation replacement of defective memory elements, the reliability of many systems may be improved. In addition, the disclosed redundancy scheme allows two or more defective memory elements from different rows or columns to be replaced with memory elements from a single redundant low or column. This provides added flexibility during the replacement process.
    Type: Grant
    Filed: October 14, 2003
    Date of Patent: March 1, 2005
    Assignee: Micron Technology, Inc.
    Inventors: Theodore Zhu, Gary Kirchner, Richard W. Swanson, Yong Lu