Patents by Inventor Sheldon C. P. Lim

Sheldon C. P. Lim 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: 7487064
    Abstract: A method that uses a goodness of fit test/measurement (e.g., correction coefficient) for process control of a test parameter (e.g., resistance). At least the minimum number of test values required to calculate a goodness of fit test is obtained. A curve is fitted for the test parameters values and the independent variable(s). A goodness of fit measurement/test (e.g., correlation coefficient) is calculated for the curve and data. The goodness of fit measurement value is used for process control. Control limits can be established on the goodness of fit measurement values. The use of the goodness of fit test is a sensitive test that can used to control processes with low level defects or small fluctuations.
    Type: Grant
    Filed: July 18, 2003
    Date of Patent: February 3, 2009
    Assignee: Chartered Semiconductor Manufacturing, Ltd.
    Inventor: Sheldon C. P. Lim
  • Patent number: 5624874
    Abstract: The properties of a diffusion barrier material layer over a semiconductor substrate are enhanced in a simple and time-effective manner by immersing the substrate in an oxidizing liquid. For a titanium-tungsten barrier metal, a dip in nitric acid for 1-60 minutes provides the metal with an oxide layer of the right thickness of 10-20 .ANG..
    Type: Grant
    Filed: October 18, 1995
    Date of Patent: April 29, 1997
    Assignee: North America Philips Corporation
    Inventors: Sheldon C. P. Lim, Stanley C. Chu
  • Patent number: 5465004
    Abstract: The size of a fusible link (22 C.sub.F) created from part of a metal layer (22) is controlled by an oxidation performed in a deposition chamber that is also used for depositing a dielectric layer (30) over the fuse structure. The metal layer serves as a diffusion barrier between semiconductor material (14 and 16) and another metal layer (24).
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: November 7, 1995
    Assignee: North American Philips Corporation
    Inventors: Sheldon C. P. Lim, Julie W. Hellstrom, Ting P. Yen
  • Patent number: 5244836
    Abstract: The present invention provides a method of forming fuse ribbons between conductive layers on a semiconductor device. The formation of these fuse ribbons may be at different levels of multiple level integrated circuits. The fuse ribbons are formed in a more precise manner than can be obtained conventionally. Resistance control can be easily achieved and significant decreases in dimensions and the use of less fuse material can be achieved.
    Type: Grant
    Filed: December 30, 1991
    Date of Patent: September 14, 1993
    Assignee: North American Philips Corporation
    Inventor: Sheldon C. P. Lim
  • Patent number: 5015604
    Abstract: The size of a fusible link (22C.sub.F) created from part of a metal layer (22) is controlled by an oxidation performed in a deposition chamber that is also used for depositing a dielectric layer (30) over the fuse structure. The metal layer serves as a diffusion barrier between semiconductor material (14 and 16) and another metal layer (24).
    Type: Grant
    Filed: August 18, 1989
    Date of Patent: May 14, 1991
    Assignee: North American Philips Corp., Signetics Division
    Inventors: Sheldon C. P. Lim, Julie W. Hellstrom, Ting P. Yen
  • Patent number: 4662986
    Abstract: A technique for producing planarized semiconductor surfaces and for isolating semiconductor islands.
    Type: Grant
    Filed: June 27, 1985
    Date of Patent: May 5, 1987
    Assignee: Signetics Corporation
    Inventor: Sheldon C. P. Lim
  • Patent number: 4569121
    Abstract: In fabricating a PROM cell, an electrical isolation mechanism (44 and 32) is formed in a semiconductive body to separate islands of an upper zone (36) of first type conductivity (N) in the body. A semiconductor impurity is introduced into one of the islands to produce a region (48) of opposite type conductivity (P) that forms a PN junction laterally bounded by the island's side boundaries. A highly resistive amorphous semiconductive layer (58) which is irreversibly switchable to a low resistive state is deposited above the region in such a manner as to be electrically coupled to the region. A path of first type conductivity extending from the PN junction through another of the islands to its upper surface is created in the body to complete the basic cell.
    Type: Grant
    Filed: March 7, 1983
    Date of Patent: February 11, 1986
    Assignee: Signetics Corporation
    Inventors: Sheldon C. P. Lim, Douglas F. Ridley, Saiyed A. Raza, George W. Conner
  • Patent number: 4569120
    Abstract: In fabricating a PROM cell, an electrical isolation mechanism (44 and 32) is formed in a semiconductive body to separate islands of an upper zone (36) of first type conductivity (N) in the body. A semiconductor is introduced into one of the islands to produce a region (48) of opposite type conductivity (P) that forms a PN junction with adjacent semiconductive material of the island. Ions are implanted to convert a surface layer (60) of the region into a highly resistive amorphous form which is irreversibly switchable to a low resistance state. A path of first type conductivity extending from the PN junction through another of the islands to its upper surface is created in the body to complete the basic cell.
    Type: Grant
    Filed: March 7, 1983
    Date of Patent: February 11, 1986
    Assignee: Signetics Corporation
    Inventors: William T. Stacy, Sheldon C. P. Lim, Kevin G. Jew
  • Patent number: 4491860
    Abstract: A film of titanitum-tungsten nitride is used to provide the dual function of a fuse link between a semiconductive device and an interconnect line in a memory array and of a barrier metal between another metal and a semiconductor region.
    Type: Grant
    Filed: April 23, 1982
    Date of Patent: January 1, 1985
    Assignee: Signetics Corporation
    Inventor: Sheldon C. P. Lim