Growth of Au thin film on Cu-modified Si(1 1 1) surface

Miniaturizing of electronic devices requires that conductive elements maintain advanced electrical characteristics upon reducing their geometrical sizes. For gold, which is valued for its high electrical conductivity and stability against ambient conditions, creation of extra-thin films on silicon is hampered by formation of the quite complex Au/Si interface. In the present work, by forming a Si(1 1 1)5.55 × 5.55-Cu surface reconstruction prior to Au deposition we formed Au films with smoother surface morphology and higher surface conductivity compared to Au film grown on a pristine Si(1 1 1)7 × 7 surface. Scanning tunnelling microscopy and four-point probe measurements were used to characterize the growth mode of the Au film on a Si(1 1 1)5.55 × 5.55-Cu reconstruction at room temperature.