Studies of carbon ion self-implantation into hydrogenated amorphous carbonfilms

The properties of polymer-like amorphous hydrogenated carbon thin films wit h low defect density have been studied. These films were implanted with car bon ions with a dose range of 10(12)-10(16) cm(-2). The purpose of the stud y is to investigate the effects of ion beam damage on this type of him. Opt ical absorption measurements observe a narrowing of the optical band gap, s uggesting the introduction of a large number of defect states subsequent to the implantation resulting in the broadening of the band tails, only after a threshold ion dose of 10(15) cm(-2). Nuclear reaction analysis suggests also a reduction in the hydrogen content of the him which coincides with fi lm thinning. (C) 2000 Elsevier Science S.A. All rights reserved.