Abstract: A method for annealing amorphous silicon film to produce polycrystalline film suitable for thin-film transistors fabricated on glass substrates is provided. The method involves using the selective location of nickel on a predetermined region of silicon to define the pattern of the lateral growth front as the silicon is crystallized. The method defines the resistivity of the silicide formed. The method also defines a specific range of nickel thicknesses to form the nickel silicide. A minimum thickness ensures that a continuous layer of nickel silicide exists on the growth front to promote an isotropic lateral growth front to form a crystalline film having high electron mobility. A maximum thickness limit reduces the risk of nickel silicide enclaves in the crystalline film to degrade the leakage current. Strategic placement of the nickel helps prevent nickel silicide contamination of the transistor channel regions, which degrade the leakage current.
Type:
Grant
Filed:
July 15, 1997
Date of Patent:
August 17, 1999
Assignees:
Sharp Laboratories of America, Inc., Sharp Kabushiki Kaisha