Atomic oxygen treatment of carbon containing low-k dielectric materials to facilitate manganese silicate barrier formation

The surface treatment of low-k dielectric layers by exposure to atomic oxygen is presented as an alternative to plasma based treatments prior to barrier layer formation. High carbon content porous low-k dielectric films were subjected to increasing exposures of atomic oxygen and X-ray photoelectron spectroscopy (XPS) studies reveal both the depletion of carbon and the addition of oxygen at the surface. This treatment is shown to be thermally stable up to 400 °C. High resolution electron energy loss spectroscopy (EELS) elemental profiles show the removal of carbon from the surface of the treated films to a depth of ~ 20 nm. In a separate experiment manganese (~1-2 nm) was deposited on an oxygen treated substrate and thermally annealed to form MnSiO₃. It is shown that the modification of the low-k surface made the chemical identification of MnSiO₃ formation possible by XPS analysis.