Resistivity of sub-50 nm copper lines epitaxially grown on Si(100) substrate

We report the creation of 50 nm thick epitaxial Cu lines with line widths ranging from 20 nm to 120 nm on Si(100) substrate using a combination of electron beam lithography, oblique angle deposition, and lift-off techniques. The increase of measured resistivity as a function of decreasing line width is dominated by surface scattering that is completely diffuse. The measured resistivity of the 20 nm wide lines is ~ 4 μΩ-cm.