Patents Assigned to Elm Technology Corporation
  • Patent number: 5654127
    Abstract: Each transistor or logic unit on an integrated circuit wafer is tested prior to interconnect metallization. By means of CAD software, the transistor or logic units placement net list is revised to substitute redundant defect-free logic units for defective ones. Then the interconnect metallization is laid down and patterned under control of a CAD computer system. Each die in the wafer thus has its own interconnect scheme, although each die is functionally equivalent, and yields are much higher than with conventional testing at the completed circuit level.The individual transistor or logic unit testing is accomplished by a specially fabricated flexible tester surface made in one embodiment of several layers of flexible silicon dioxide, each layer containing vias and conductive traces leading to thousands of microscopic metal probe points on one side of the test surface. The probe points electrically contact the contacts on the wafer under test by fluid pressure.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: August 5, 1997
    Assignee: ELM Technology Corporation
    Inventor: Glenn J. Leedy
  • Patent number: 5637907
    Abstract: General purpose methods for the fabrication of integrated circuits from flexible membranes formed of very thin low stress dielectric materials, such as silicon dioxide or silicon nitride, and semiconductor layers. Semiconductor devices are formed in a semiconductor layer of the membrane. The semiconductor membrane layer is initially formed from a substrate of standard thickness, and all but a thin surface layer of the substrate is then etched or polished away. In another version, the flexible membrane is used as support and electrical interconnect for conventional integrated circuit die bonded thereto, with the interconnect formed in multiple layers in the membrane. Multiple die can be connected to one such membrane, which is then packaged as a multi-chip module. Other applications are based on (circuit) membrane processing for bipolar and MOSFET transistor fabrication, low impedance conductor interconnecting fabrication, flat panel displays, maskless (direct write) lithography, and 3D IC fabrication.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 10, 1997
    Assignee: ELM Technology Corporation
    Inventor: Glenn J. Leedy
  • Patent number: 5633209
    Abstract: General purpose methods for the fabrication of integrated circuits from flexible membranes formed of very thin low stress dielectric materials, such as silicon dioxide or silicon nitride, and semiconductor layers. Semiconductor devices are formed in a semiconductor layer of the membrane. The semiconductor membrane layer is initially formed from a substrate of standard thickness, and all but a thin surface layer of the substrate is then etched or polished away. In another version, the flexible membrane is used as support and electrical interconnect for conventional integrated circuit die bonded thereto, with the interconnect formed in multiple layers in the membrane. Multiple die can be connected to one such membrane, which is then packaged as a multi-chip module. Other applications are based on (circuit) membrane processing for bipolar and MOSFET transistor fabrication, low impedance conductor interconnecting fabrication, flat panel displays, maskless (direct write) lithography, and 3D IC fabrication.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 27, 1997
    Assignee: ELM Technology Corporation
    Inventor: Glenn J. Leedy
  • Patent number: 5629137
    Abstract: Each transistor or logic unit on an integrated circuit wafer is tested prior to interconnect metallization. By means of CAD software, the transistor or logic units placement net list is revised to substitute redundant defect-free logic units for defective ones. Then the interconnect metallization is laid down and patterned under control of a CAD computer system. Each die in the wafer thus has its own interconnect scheme, although each die is functionally equivalent, and yields are much higher than with conventional testing at the completed circuit level.The individual transistor or logic unit testing is accomplished by a specially fabricated flexible tester surface made in one embodiment of several layers of flexible silicon dioxide, each layer containing vias and conductive traces leading to thousands of microscopic metal probe points on one side of the test surface. The probe points electrically contact the contacts on the wafer under test by fluid pressure.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 13, 1997
    Assignee: ELM Technology Corporation
    Inventor: Glenn J. Leedy