Influence of plasma treatment on low-k dielectric films in semiconductor manufacturing

High-resolution X-ray reflectometry (XRR) at SSLS' XDD beamline has been used to characterise films of low dielectric constant materials. In this paper, we present results of reflectometry studies of ultra-low k dielectric films made of commercial SiLK and carbon doped silicon oxide, i.e. SiOCH (MSQ, methylsilsesquioxane). Reflectivity reveals that the films can suffer severe roughening in surface and change in their thickness depending on different plasma treatments. The densities of the layers can change, which will lead to changes in the k-values. The results are being used for the selection and optimization of plasma processes used in semiconductor manufacturing.