Patents by Inventor Wai-Ming Johnson Kan

Wai-Ming Johnson Kan 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: 8324698
    Abstract: A STT-MRAM integration scheme is disclosed wherein the connection between a MTJ and CMOS metal is simplified by forming an intermediate via contact (VAC) on a CMOS landing pad, a metal (VAM) pad that contacts and covers the VAC, and a MTJ on the VAM. A dual damascene process is performed to connect BIT line metal to CMOS landing pads through VAC/VAM/MTJ stacks in a device region, and to connect BIT line connection pads to CMOS connection pads through BIT connection vias outside the device region. The VAM pad is a single layer or composite made of Ta, TaN, or other conductors which serves as a diffusion barrier, has a highly smooth surface for MTJ formation, and provides excellent selectivity with refill dielectric materials during a chemical mechanical polish process. Each VAC is from 500 to 3000 Angstroms thick to minimize additional circuit resistance and minimize etch burden.
    Type: Grant
    Filed: January 4, 2011
    Date of Patent: December 4, 2012
    Assignee: MagIC Technologies, Inc.
    Inventors: Tom Zhong, Chyu-Jiuh Torng, Rongfu Xiao, Adam Zhong, Wai-Ming Johnson Kan, Daniel Liu
  • Patent number: 8183061
    Abstract: A STT-MRAM integration scheme is disclosed wherein the connection between a MTJ and CMOS metal is simplified by forming an intermediate via contact (VAC) on a CMOS landing pad, a metal (VAM) pad that contacts and covers the VAC, and a MTJ on the VAM. A dual damascene process is performed to connect BIT line metal to CMOS landing pads through VAC/VAM/MTJ stacks in a device region, and to connect BIT line connection pads to CMOS connection pads through BIT connection vias outside the device region. The VAM pad is a single layer or composite made of Ta, TaN, or other conductors which serves as a diffusion barrier, has a highly smooth surface for MTJ formation, and provides excellent selectivity with refill dielectric materials during a chemical mechanical polish process. Each VAC is from 500 to 3000 Angstroms thick to minimize additional circuit resistance and minimize etch burden.
    Type: Grant
    Filed: February 7, 2011
    Date of Patent: May 22, 2012
    Assignee: MagIC Technologies, Inc.
    Inventors: Tom Zhong, Chyu-Jiuh Torng, Rongfu Xiao, Adam Zhong, Wai-Ming Johnson Kan, Daniel Liu
  • Publication number: 20110129946
    Abstract: A STT-MRAM integration scheme is disclosed wherein the connection between a MTJ and CMOS metal is simplified by forming an intermediate via contact (VAC) on a CMOS landing pad, a metal (VAM) pad that contacts and covers the VAC, and a MTJ on the VAM. A dual damascene process is performed to connect BIT line metal to CMOS landing pads through VAC/VAM/MTJ stacks in a device region, and to connect BIT line connection pads to CMOS connection pads through BIT connection vias outside the device region. The VAM pad is a single layer or composite made of Ta, TaN, or other conductors which serves as a diffusion barrier, has a highly smooth surface for MTJ formation, and provides excellent selectivity with refill dielectric materials during a chemical mechanical polish process. Each VAC is from 500 to 3000 Angstroms thick to minimize additional circuit resistance and minimize etch burden.
    Type: Application
    Filed: February 7, 2011
    Publication date: June 2, 2011
    Inventors: Tom Zhong, Chyu-Jiuh Torng, Rongfu Xiao, Adam Zhong, Wai-Ming Johnson Kan, Daniel Liu
  • Publication number: 20110101478
    Abstract: A STT-MRAM integration scheme is disclosed wherein the connection between a MTJ and CMOS metal is simplified by forming an intermediate via contact (VAC) on a CMOS landing pad, a metal (VAM) pad that contacts and covers the VAC, and a MTJ on the VAM. A dual damascene process is performed to connect BIT line metal to CMOS landing pads through VAC/VAM/MTJ stacks in a device region, and to connect BIT line connection pads to CMOS connection pads through BIT connection vias outside the device region. The VAM pad is a single layer or composite made of Ta, TaN, or other conductors which serves as a diffusion barrier, has a highly smooth surface for MTJ formation, and provides excellent selectivity with refill dielectric materials during a chemical mechanical polish process. Each VAC is from 500 to 3000 Angstroms thick to minimize additional circuit resistance and minimize etch burden.
    Type: Application
    Filed: January 4, 2011
    Publication date: May 5, 2011
    Inventors: Tom Zhong, Chyu-Jiuh Torng, Rongfu Xiao, Adam Zhong, Wai-Ming Johnson Kan, Daniel Liu
  • Patent number: 7919407
    Abstract: Described herein are novel, cost effective and scalable methods for integrating a CMOS level with a memory cell level to form a field induced MRAM device. The memory portion of the device includes N parallel word lines, which may be clad, overlaid by M parallel bit lines orthogonal to the word lines and individual patterned memory cells formed on previously patterned electrodes at the N×M intersections of the two sets of lines. The memory portion is integrated with a CMOS level and the connection between levels is facilitated by the formation of interconnecting vias between the N×M electrodes and corresponding pads in the CMOS level and by word line connection pads in the memory device level and corresponding metal pads in the CMOS level.
    Type: Grant
    Filed: November 17, 2009
    Date of Patent: April 5, 2011
    Assignee: MagIC Technologies, Inc.
    Inventors: Tom Zhong, Wai-Ming Johnson Kan, Daniel Liu, Adam Zhong, Chyu-Jiuh Torng
  • Patent number: 7884433
    Abstract: A STT-MRAM integration scheme is disclosed wherein the connection between a MTJ and CMOS metal is simplified by forming an intermediate via contact (VAC) on a CMOS landing pad, a metal (VAM) pad that contacts and covers the VAC, and a MTJ on the VAM. A dual damascene process is performed to connect BIT line metal to CMOS landing pads through VAC/VAM/MTJ stacks in a device region, and to connect BIT line connection pads to CMOS connection pads through BIT connection vias outside the device region. The VAM pad is a single layer or composite made of Ta, TaN, or other conductors which serves as a diffusion barrier, has a highly smooth surface for MTJ formation, and provides excellent selectivity with refill dielectric materials during a chemical mechanical polish process. Each VAC is from 500 to 3000 Angstroms thick to minimize additional circuit resistance and minimize etch burden.
    Type: Grant
    Filed: October 31, 2008
    Date of Patent: February 8, 2011
    Assignee: MagIC Technologies, Inc.
    Inventors: Tom Zhong, Chyu-Jiuh Torng, Rongfu Xiao, Adam Zhong, Wai-Ming Johnson Kan, Daniel Liu
  • Publication number: 20100109106
    Abstract: A STT-MRAM integration scheme is disclosed wherein the connection between a MTJ and CMOS metal is simplified by forming an intermediate via contact (VAC) on a CMOS landing pad, a metal (VAM) pad that contacts and covers the VAC, and a MTJ on the VAM. A dual damascene process is performed to connect BIT line metal to CMOS landing pads through VAC/VAM/MTJ stacks in a device region, and to connect BIT line connection pads to CMOS connection pads through BIT connection vias outside the device region. The VAM pad is a single layer or composite made of Ta, TaN, or other conductors which serves as a diffusion barrier, has a highly smooth surface for MTJ formation, and provides excellent selectivity with refill dielectric materials during a chemical mechanical polish process. Each VAC is from 500 to 3000 Angstroms thick to minimize additional circuit resistance and minimize etch burden.
    Type: Application
    Filed: October 31, 2008
    Publication date: May 6, 2010
    Inventors: Tom Zhong, Chyu-Jiuh Torng, Rongfu Xiao, Adam Zhong, Wai-Ming Johnson Kan, Daniel Liu