IMPLANTATION EFFECT OF DIAMOND-LIKE CARBON-FILMS BY 110 KEV NITROGEN-IONS

Diamond-like carbon films, grown on microscope slides by a dual-ion be am sputtering system, were implanted by 110 keV N+ under the doses of 1 x 10(15), 1 x 10(16) and 1 x 10(17) ions cm(-2) respectively. The im plantation induced changes in electrical resistivity of the films and in infrared (IR) transmittance of the specimens were investigated as a function of implantation dose. The structural changes of the films we re also studied using IR spectroscopy and Raman spectroscopy. It was o bserved that, with the increase of implantation dose, the diamond-like carbon films display two different stages in electrical and optical b ehaviours. The first is the increase of both the film resistivity and the IR transmittance of specimen at the dose of 1 x 10(15) ions cm(-2) which, we consider, is attributed to the implantation-induced increas e of sp(3) C-H bonds. However, when the doses are higher than 1 x 10(1 5) ions cm(-2), the film resistivity and the IR transmittance of speci men decrease significantly and the decrease rates at dose range of 1 x 10(16) to 1 x 10(17) ions cm(-2) are smaller than those between 1 x 1 0(15) and 1 x 10(16) ions cm(-2). We conclude that the significant red uctions of the two parameters at high doses are caused by the decrease s of bond-angle disorder and of sp(3) C-H bonds, the increases of sp(2 ) C-C bonds dominated the crystallite size and/or number and also the sp(2) C-H bonds. The smaller decrease rates at a dose range of 1 x 10( 16) to 1 x 10(17) ions cm(-2) may be caused by further recombination o f some retained hydrogen atoms to carbon atoms.