MODIFICATION OF MAGNETRON-SPUTTERED A-SI1-XCX-H FILMS BY IMPLANTATIONOF GE+

Implantation of Ge+ ions into a-Si1-xCx:H films deposited by RF reacti ve magnetron sputtering of silicon and graphite, was carried out in or der to obtain optical contrast in the layers. The expected optical eff ect which is a transmission edge shift to the lower photon energies ac companied by a decrease of the transmission coefficient was observed. This effect is more pronounced with higher implantation doses. Ion imp lantation of Ge+ considerably increases the absorption coefficient (al pha) even for the lowest dose which is of the order of 10(15) cm(-2). This increase is most pronounced in a narrow energy region around 2.2 eV (1.8-2.4 eV). Raman, infrared (IR) and photoelectron spectroscopy ( XPS) measurements were used to study the structure and bond configurat ions of the implanted films. These measurements reveal that ion implan tation introduces an additional disorder in the films as well as leads to a chemical modification of the films, which could be related to th e changes of the optical properties.