THE EFFECT OF ION ENERGY ON THE DIAMOND-LIKE GRAPHITIC (SP(3) SP(2)) NATURE OF CARBON-FILMS DEPOSITED BY ION-BEAMS/

Ion energy is known to be a crucial parameter in the determination of properties of films deposited by ion beams. Contradictory results rega rding the optimal C ion energy for the deposition of diamond-like (sp3 -rich) carbon films have been reported: (i) about 20-40 eV by McKenzie et al., (ii) about 100-200 eV by Ishikawa et al. and (iii) about 100- 700 eV by Hirvonen et al. These data are important both for establishi ng models of carbon film growth from ion beams and for practical film depositions. In the present work pure carbon films were deposited at r oom temperature on Si using mass-selected C+ ions covering the energy region 10-300 eV. Diamond-like properties were found for the entire en ergy region 30-300 eV. A transition to graphitic properties was observ ed for ion energies lower than 30 eV.