Patents Represented by Attorney Albert Crowder
  • Patent number: 5021353
    Abstract: An improved CMOS fabrication process which uses separate masking steps to pattern N-channel and P-channel transistor gates from a single layer of conductively-doped polycrystalline silicon (poly) and incorporates self-aligned salicidation of conductive regions. The object of the improved process is to reduce the cost and improve the reliability, performance and manufacturability of CMOS devices by a process which features a dramatically reduced number of photomasking steps and which further allows self-aligned salicidation of transistor conductive regions. By processing N-channel and P-channel devices separately, the number of photomasking steps required to fabricate complete CMOS circuitry in a single-polysilicon-layer or single-metal layer process can be reduced from eleven to eight. Starting with a substrate of P-type material, N-channel devices are formed first, with unetched poly left in the future P-channel regions until N-channel processing is complete.
    Type: Grant
    Filed: February 26, 1990
    Date of Patent: June 4, 1991
    Assignee: Micron Technology, Inc.
    Inventors: Tyler A. Lowrey, Dermot M. Durcan, Trung T. Doan, Gordon A. Haller, Mark E. Tuttle