Ion implantation induced modification of optical properties in single-crystal diamond studied by coherent acoustic phonon spectroscopy

Abstract

Single-crystal CVD diamond specimens were implanted with 1-MeV He+ ions at fluences ranging from 1014 to 1016 cm−2 and analyzed using coherent acoustic phonon spectroscopy. The coherent acoustic phonon response varies greatly with implantation fluence and provides depth-dependent information about the implantation defect-induced modification of diamond's optical characteristics. The results indicate an increase in the real and imaginary refractive index, as well as a sign reversal of the photoelastic coefficients at higher levels of implantation damage. These studies provide insight into the application of ion implantation to the fabrication of diamond-based photonic devices.