Cross-sectional Raman microscopy of MeV implanted diamond

The defect structures created in diamond by MeV He ion implantation are studied using Raman microscopy. The diamond was irradiated edge on, and the micro-Raman spectra were collected in a direction perpendicular to the implantation direction. This 'cross-sectional' geometry allowed the Raman spectrum of the damage to be resolved as a function of depth from the ion implanted surface. Both the position and the FWHM of the first order Raman mode at 1332 cm(-1) were found to scale linearly with dose; a result readily interpretable as defect induced strain in the implanted layer. The measurements thus provide the depth profile of ion implanted damage in MeV irradiated diamond, and allow a direct test of the accuracy of theoretical models, such as TRIM, for the assessment of damage in ion irradiated diamond.