Diamond windows prepared using hot filament chemical vapor deposition were irradiated with Au and Ag ions of energy 100 and 130MeV, respectively with fluences of 1010 to 3 x 1013/cm2. Scanning electron microscopic images showed substantial damage at the surface of the windows irradiated with Au+ of energy 100MeV and fluence of 3 x 1013/cm2. At some locations on the diamond windows deposited at 16kPa, the surface layer appeared to have melted and flowed like a liquid exposing small crystallites underneath. Raman spectra of windows after irradiation showed i) a decrease in the intensity of the one-phonon line at 1332/cm along with an increase in its half width; ii) substantial reduction in the intensity of the graphite G band; and, iii) the appearance of a new band at 667/cm. The band at 667/cm did not have a corresponding Stokes line and was therefore identified as a photoluminescence band. The ion induced damage and localized melting of chemical vapor deposited diamond windows were explained in terms of the thermal spike model.

Melting and Defect Generation in Chemical Vapor Deposited Diamond Due to Irradiation with 100MeV Au+ and Ag+ Ions. D.S.Misra, U.Palnitkar, P.K.Tyagi, M.K.Singh, E.Titus, D.K.Avasthi, P.Vasa, P.Ayyub: Thin Solid Films, 2006, 503[1-2], 121-6