TY - JOUR
T1 - Amorphous diamond films deposited by pulsed-laser ablation
T2 - Proceedings of the 1998 MRS Spring Meeting
AU - Lowndes, Douglas H.
AU - Merkulov, Vladimir I.
AU - Puretzky, A. A.
AU - Geohegan, D. B.
AU - Jellison, G. E.
AU - Rouleau, C. M.
AU - Thundat, T.
PY - 1998
Y1 - 1998
N2 - A systematic study has been made of changes in the bonding and optical properties of hydrogen-free tetrahedral amorphous carbon (ta-C) films, as a function of the kinetic energy of the incident carbon ions measured under film-deposition conditions. Ion probe measurements of the carbon ion kinetic energies produced by ArF and KrF laser ablation of graphite are compared under identical beam-focusing conditions. Much higher C+ kinetic energies are produced by ArF-laser ablation than by KrF for any given fluence and spot size. Electron energy loss spectroscopy and scanning ellipsometry measurements of the sp3 bonding fraction, plasmon energy, and optical properties reveal a well-defined optimum kinetic energy of 90 eV to deposit ta-C films having the largest sp3 fraction and the widest optical (Tauc) energy gap (equivalent to minimum near-gap optical absorption). Tapping-mode atomic force microscope measurements show that films deposited at near-optimum kinetic energy are extremely smooth, with rms roughness of only approximately 1 angstrom over distances of several hundred nm, and are relatively free of particulates.
AB - A systematic study has been made of changes in the bonding and optical properties of hydrogen-free tetrahedral amorphous carbon (ta-C) films, as a function of the kinetic energy of the incident carbon ions measured under film-deposition conditions. Ion probe measurements of the carbon ion kinetic energies produced by ArF and KrF laser ablation of graphite are compared under identical beam-focusing conditions. Much higher C+ kinetic energies are produced by ArF-laser ablation than by KrF for any given fluence and spot size. Electron energy loss spectroscopy and scanning ellipsometry measurements of the sp3 bonding fraction, plasmon energy, and optical properties reveal a well-defined optimum kinetic energy of 90 eV to deposit ta-C films having the largest sp3 fraction and the widest optical (Tauc) energy gap (equivalent to minimum near-gap optical absorption). Tapping-mode atomic force microscope measurements show that films deposited at near-optimum kinetic energy are extremely smooth, with rms roughness of only approximately 1 angstrom over distances of several hundred nm, and are relatively free of particulates.
UR - http://www.scopus.com/inward/record.url?scp=0032318367&partnerID=8YFLogxK
U2 - 10.1557/proc-526-325
DO - 10.1557/proc-526-325
M3 - Conference article
AN - SCOPUS:0032318367
SN - 0272-9172
VL - 526
SP - 325
EP - 330
JO - Materials Research Society Symposium - Proceedings
JF - Materials Research Society Symposium - Proceedings
Y2 - 13 April 1998 through 16 April 1998
ER -