Microstructure of copper films on silicon with an ion beam assisted deposited intermediate copper layer

Abstract Cu intermediate layers (IL) were deposited by ion beam assisted deposition (IBAD) on a Si(100) substrate before Cu surface films (SF) were deposited by electron gun and their effect on the microstructure of the Cu SF was studied. The argon ion energy and current density of IBAD were 2–20 keV and 45 μA cm 2 , respectively. The thickness of the Cu SF was 350 nm. The Cu SF, if there is no IBAD of Cu IL, have a strong preferential orientation of the Cu(200) plane parallel to the Si(100) surface. The IBAD of Cu IL changes this orientation to a (111) orientation. For an IBAD argon ion energy of 15 keV, the Cu SF has a maximum value of the X-ray diffraction (XRD) peak-height ratio, i.e. I(111) I(200) = 41 . Scanning electron microscope (SEM) analysis shows that the Cu films with Cu IL are rougher than those without Cu IL.