Implantation of Sn+ into a-Si1.xCx:H films deposited by RF magnetron sputtering of silicon and graphite was carried out in order to obtain optical contrast in the layers. The expected optical effect which is an absorption edge shift to the lower photon energies accompanied by a considerable increase of the absorption coefficient was observed even for the lowest dose - 1015cm-2. This effect is more pronounced with increase of the dose. Infrared (IR) and photoelectron spectroscopy (XPS) measurements was used to study the bond configurations of implanted films. These measurements reveal that ion implantation introduces an additional disorder in the films as well as leads to their chemical modification, which could be related to the changes of the optical properties.