Patents by Inventor Kia-Seng Low

Kia-Seng Low 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: 7125790
    Abstract: Low-k dielectric materials are incorporated as an insulator material between bit lines and an inter-level dielectric material. The device is first processed in a known manner, up to and including the deposition and anneal of the bit line metal, using a higher dielectric constant material that can withstand the higher temperature process steps as the insulator between the bit lines. Then, the higher dielectric constant material is removed using an etch that is selective to the bit line metal, and the low-k dielectric material is deposited. The low-k material may then be planarized to the top of the bit lines, and further low-k material deposited as an inter-level dielectric. Alternatively, sufficient low-k material is deposited in a single step to both fill the gaps between the bit lines as well as serve as an inter-level dielectric, and then the low-k dielectric material is planarized. Standard processing may then be carried out.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: October 24, 2006
    Assignee: Infineon Technologies AG
    Inventors: Kia Seng Low, Larry Nesbit, George C. Feng
  • Patent number: 7097777
    Abstract: A method of forming a magnetic switching device is provided. The method includes depositing a bilayer hardmask, which may comprise a first mask layer of titanium nitride with a second mask layer of tungsten formed thereon. A first lithography process is performed to pattern the second mask layer, and a second lithography process is performed to pattern the first mask layer. Thereafter, the magnetic tunnel junction stack may be patterned in accordance with the first mask layer. An etching process may be performed to further pattern the first mask layer in accordance with the second mask layer. An optional passivation layer may be formed over the first mask layer and the second mask layer.
    Type: Grant
    Filed: March 2, 2005
    Date of Patent: August 29, 2006
    Assignees: Infineon Technologies AG, International Business Machines Corporation
    Inventors: Gregory Costrini, John P. Hummel, George Stojakovic, Kia-Seng Low
  • Patent number: 7087438
    Abstract: The invention relates to a method of encapsulating conductive lines of semiconductor devices and a structure thereof. An encapsulating protective material, such as TaN, Ta, Ti, TiN, or combinations thereof is disposed over conductive lines of a semiconductor device. The encapsulating protective material protects the conductive lines from harsh etch chemistries when a subsequently deposited material layer is patterned and etched. The encapsulating protective material is conductive and may be left remaining in the completed semiconductor device. The encapsulating material is patterned using a masking material, and processing of the semiconductor device is then continued. The masking material may be left remaining in the structure as part of a subsequently deposited insulating material layer.
    Type: Grant
    Filed: July 26, 2004
    Date of Patent: August 8, 2006
    Assignees: Infineon Technologies AG, International Business Machines Corporation
    Inventors: Ihar Kasko, Kia-Seng Low, John P. Hummel
  • Publication number: 20060019431
    Abstract: A method of encapsulating conductive lines of semiconductor devices and a structure thereof. An encapsulating protective material comprising TaN, Ta, Ti, TiN, or combinations thereof is disposed over conductive lines of a semiconductor device. The encapsulating protective material protects the conductive lines from harsh etch chemistries when a subsequently deposited material layer is patterned and etched. The encapsulating protective material is conductive and may be left remaining in the completed semiconductor device. The encapsulating material is patterned using a masking material, and processing of the semiconductor device is then continued. The masking material may be left remaining in the structure as part of a subsequently deposited insulating material layer.
    Type: Application
    Filed: July 26, 2004
    Publication date: January 26, 2006
    Inventors: Ihar Kasko, Kia-Seng Low, John Hummel
  • Patent number: 6985384
    Abstract: A magneto resistive memory device is fabricated by etching a blanket metal stack comprised of a buffer layer, pinned magnetic layer, a tunnel barrier layer and a free magnetic layer. The problem of junction shorting from resputtered metal during the etching process is eliminated by formation of a protective spacer covering the side of the freelayer and tunnel barrier interface. The spacer is formed following the first etch through the free layer which stops on the barrier layer. After spacer formation a second etch is made to isolate the device. The patterning of the device tunnel junction is made using a disposable mandrel method that enables a self-aligned contact to be made following the completion of the device patterning process.
    Type: Grant
    Filed: October 1, 2002
    Date of Patent: January 10, 2006
    Assignee: International Business Machines Corporation
    Inventors: Gregory Costrini, John Hummel, Kia-Seng Low, Igor Kasko, Frank Findeis, Wolfgang Raberg
  • Patent number: 6974770
    Abstract: Self-aligning vias and trenches etched between adjacent lines of metallization allows the area of the dielectric substrate allocated to the via or trench to be significantly reduced without increasing the possibility of electrical shorts to the adjacent lines of metallization.
    Type: Grant
    Filed: June 20, 2003
    Date of Patent: December 13, 2005
    Assignees: Infineon Technologies AG, International Business Machines Corporation
    Inventors: Gregory Costrini, Kia-Seng Low, David L. Rath, Michael C. Gaidis, Walter Glashauser
  • Publication number: 20050207064
    Abstract: A method of forming a magnetic switching device is provided. The method includes depositing a bilayer hardmask, which may comprise a first mask layer of titanium nitride with a second mask layer of tungsten formed thereon. A first lithography process is performed to pattern the second mask layer, and a second lithography process is performed to pattern the first mask layer. Thereafter, the magnetic tunnel junction stack may be patterned in accordance with the first mask layer. An etching process may be performed to further pattern the first mask layer in accordance with the second mask layer. An optional passivation layer may be formed over the first mask layer and the second mask layer.
    Type: Application
    Filed: March 2, 2005
    Publication date: September 22, 2005
    Inventors: Gregory Costrini, John Hummel, George Stojakovic, Kia-Seng Low
  • Patent number: 6884630
    Abstract: Magnetic tunnel junction devices can be fabricated using a two-step deposition process wherein respective portions of the magnetic tunnel junction stack are defined independently of one another.
    Type: Grant
    Filed: January 21, 2003
    Date of Patent: April 26, 2005
    Assignees: Infineon Technologies AG, Internation Business Machines Corporation
    Inventors: Arunava Gupta, Kia-Seng Low
  • Patent number: 6858441
    Abstract: A method of manufacturing a resistive semiconductor memory device (100), comprising depositing an insulating layer (132) over a workpiece (30), and defining a pattern for a plurality of alignment marks (128) and a plurality of conductive lines (112) within the insulating layer (132). A conductive material is deposited over the wafer to fill the alignment mark (128) and conductive line (112) patterns. The insulating layer (132) top surface is chemically-mechanically polished to remove excess conductive material from the insulating layer (132) and form conductive lines (112), while leaving conductive material remaining within the alignment marks (128). A masking layer (140) is formed over the conductive lines (112), and at least a portion of the conductive material is removed from within the alignment marks (128). The alignment marks (128) are used for alignment of subsequently deposited layers of the resistive memory device (100).
    Type: Grant
    Filed: September 4, 2002
    Date of Patent: February 22, 2005
    Assignee: Infineon Technologies AG
    Inventors: Joachim Nuetzel, Xian J. Ning, Kia-Seng Low, Gill Yong Lee, Rajiv M. Ranade, Ravikumar Ramachandran
  • Patent number: 6846683
    Abstract: A semiconductor device (118) and method of fabrication thereof, wherein a plurality of conductive lines (124) are formed over a workpiece, a surface-smoothing conductive material (140) is disposed over the conductive lines (124), and a magnetic material (132) disposed is over the surface-smoothing conductive material (140). The surface-smoothing conductive material (140) has a smaller grain structure than the underlying conductive lines (124). The surface-smoothing conductive material (140) is polished so that the surface-smoothing conductive material (140) has a texturally smoother surface than the surface of the conductive lines (124).
    Type: Grant
    Filed: May 10, 2002
    Date of Patent: January 25, 2005
    Assignee: Infineon Technologies AG
    Inventor: Kia-Seng Low
  • Publication number: 20040259358
    Abstract: Self-aligning vias and trenches etched between adjacent lines of metallization allows the area of the dielectric substrate allocated to the via or trench to be significantly reduced without increasing the possibility of electrical shorts to the adjacent lines of metallization.
    Type: Application
    Filed: June 20, 2003
    Publication date: December 23, 2004
    Inventors: Gregory Costrini, Kia-Seng Low, David L. Rath, Michael C. Gaidis, Walter Glashauser
  • Patent number: 6768150
    Abstract: A magnetic memory cell is disclosed. The memory cell includes first conductor and second conductors coupled to first and second electrodes of a magnetic element. A plurality of memory cells is interconnected by first and second conductors to form a memory array or block. The second conductor is coupled to the second electrode via a conductive strap having a fuse portion. The fuse portion can be blown to sever the connection between the second conductor and magnetic element, Nitride.
    Type: Grant
    Filed: April 17, 2003
    Date of Patent: July 27, 2004
    Assignee: Infineon Technologies Aktiengesellschaft
    Inventors: Kia Seng Low, Joerg Dietrich Schmid
  • Patent number: 6743642
    Abstract: A method for manufacturing a magnetoresistive random access memory (MRAM) cell is disclosed, which alleviates the problem of Neel coupling caused by roughness in the interface between the tunnel junction layer and the magnetic layers. The method includes depositing first and second barrier layers on the conductor, wherein the first barrier layer has a polish rate different from that of the second barrier layer. The second barrier layer is then essentially removed by chemical mechanical polishing (CMP), leaving a very smooth and uniform first barrier layer. When the magnetic stack is then formed on the polished first barrier layer, interfacial roughness is not translated to the tunnel junction layer, and no corruption of magnetization is experienced.
    Type: Grant
    Filed: November 6, 2002
    Date of Patent: June 1, 2004
    Assignees: International Business Machines Corporation, Infineon AG
    Inventors: Gregory Costrini, John Hummel, Kia-Seng Low, Mahadevaiyer Krishnan
  • Patent number: 6740539
    Abstract: A structure and method for an insulator layer having carbon-graded layers above a substrate is disclosed, wherein the concentration of carbon increases in each successive carbon-graded layer above the substrate. The insulator comprises a low-k dielectric having a dielectric constant less than 3.3. The carbon-graded layer increases adhesion between the substrate and the insulator and between the insulator and the conductor layer. The structure may also include stabilization interfaces between the carbon-graded layers. More specifically, the carbon-graded layers include a first layer adjacent the substrate having a carbon content between about 5% and 20%, a second layer above the first layer having a carbon content between about 10% and 30%, and a third layer above the second layer having a carbon content between about 20% and 40%.
    Type: Grant
    Filed: February 13, 2003
    Date of Patent: May 25, 2004
    Assignees: International Business Machines Corporation, Infineon Technologies A.G.
    Inventors: Richard A. Conti, Prakash Chimanlal Dev, David M. Dobuzinsky, Daniel C. Edelstein, Gill Y. Lee, Kia-Seng Low, Padraic C. Shafer, Alexander Simpson, Peter Wrschka
  • Publication number: 20040087039
    Abstract: Magnetic tunnel junction devices can be fabricated using a two-step deposition process wherein respective portions of the magnetic tunnel junction stack are defined independently of one another.
    Type: Application
    Filed: January 21, 2003
    Publication date: May 6, 2004
    Inventors: Arunava Gupta, Kia-Seng Low
  • Publication number: 20040084400
    Abstract: Patterning metal stack layers of a magnetic switching device to enable a critical lithography level to be made on planar substrate without any topography and enable a second lithography step without topography from a top patterned hardmask, comprising:
    Type: Application
    Filed: October 30, 2002
    Publication date: May 6, 2004
    Inventors: Gregory Costrini, John P. Hummel, George Stojakovic, Kia-Seng Low
  • Publication number: 20040087038
    Abstract: A method for manufacturing a magnetoresistive random access memory (MRAM) cell is disclosed, which alleviates the problem of Neel coupling caused by roughness in the interface between the tunnel junction layer and the magnetic layers. The method comprises depositing first and second barrier layers on the conductor, wherein the first barrier layer has a polish rate different from that of the second barrier layer. The second barrier layer is then essentially removed by chemical mechanical polishing (CMP), leaving a very smooth and uniform first barrier layer. When the magnetic stack is then formed on the polished first barrier layer, interfacial roughness is not translated to the tunnel junction layer, and no corruption of magnetization is experienced.
    Type: Application
    Filed: November 6, 2002
    Publication date: May 6, 2004
    Applicants: INTERNATIONAL BUSINESS MACHINES CORPORATION, INFINEON TECHNOLOGIES NORTH AMERICA CORP.
    Inventors: Gregory Costrini, John Hummel, Kia-Seng Low, Mahadevaiyer Krishnan
  • Publication number: 20040063223
    Abstract: A magneto resistive memory device is fabricated by etching a blanket metal stack comprised of a buffer layer, pinned magnetic layer, a tunnel barrier layer and a free magnetic layer. The problem of junction shorting from resputtered metal during the etching process is eliminated by formation of a protective spacer covering the side of the freelayer and tunnel barrier interface. The spacer is formed following the first etch through the free layer which stops on the barrier layer. After spacer formation a second etch is made to isolate the device. The patterning of the device tunnel junction is made using a disposable mandrel method that enables a self-aligned contact to be made following the completion of the device patterning process.
    Type: Application
    Filed: October 1, 2002
    Publication date: April 1, 2004
    Applicants: International Business Machines Corporation, Infineon Technologies North America Corp.
    Inventors: Gregory Costrini, John Hummel, Kia-Seng Low
  • Publication number: 20040043579
    Abstract: A method of manufacturing a resistive semiconductor memory device (100), comprising depositing an insulating layer (132) over a workpiece (30), and defining a pattern for a plurality of alignment marks (128) and a plurality of conductive lines (112) within the insulating layer (132). A conductive material is deposited over the wafer to fill the alignment mark (128) and conductive line (112) patterns. The insulating layer (132) top surface is chemically-mechanically polished to remove excess conductive material from the insulating layer (132) and form conductive lines (112), while leaving conductive material remaining within the alignment marks (128). A masking layer (140) is formed over the conductive lines (112), and at least a portion of the conductive material is removed from within the alignment marks (128). The alignment marks (128) are used for alignment of subsequently deposited layers of the resistive memory device (100).
    Type: Application
    Filed: September 4, 2002
    Publication date: March 4, 2004
    Inventors: Joachim Nuetzel, Xian J. Ning, Kia-Seng Low, Gill Yong Lee, Rajiv M. Ranade, Ravikumar Ramachandran
  • Publication number: 20040021188
    Abstract: A semiconductor device (100) and method of fabrication thereof, wherein a plurality of first conductive lines (116) are formed in a dielectric layer (112) over a substrate (110), and an insulating cap layer (140) is disposed over the first conductive lines (116) and exposed portions of the dielectric layer (112). The insulating cap layer (140) is patterned and etched to expose stack portions of the first conductive lines (116). A conductive cap layer (144) is deposited over the exposed portions of the first conductive lines (116). A magnetic material stack (118) is disposed over the insulating cap layer (140), and the magnetic material stack is etched to form magnetic stacks. The insulating cap layer (140) and conductive cap layer (144) protect the underlying first conductive line (116) material during the etching processes.
    Type: Application
    Filed: July 31, 2002
    Publication date: February 5, 2004
    Applicants: Infineon Technologies North America Corp., International Business Machines Corporation
    Inventors: Kia-Seng Low, John P. Hummel, Igor Kasko, Gregory Costrini