Optical confinement achieved in ZnO crystal by O^+ ions implantation: analysis of waveguide formation and properties

Abstract

Optical confinement in ZnO crystal was observed by O(+) implantation with different MeV energies and doses. Planar optical waveguides were formed in the as-implanted ZnO samples. The optical properties of the planar waveguide were investigated by the prism-coupling and the end-face coupling methods at the wavelength of 633 nm. The crystal lattice damage in the guiding region caused by the O(+) ions implantation was analyzed by the Rutherford backscattering/Channeling technique, results show that even high dose at 2 × 10(15) ions/cm(2) can hardly produce defect in near surface of ZnO. A theoretical model is developed to explain the principle of waveguide formation in ZnO crystal and the refractive index profile in the implanted waveguide was reconstructed accordingly. The experimental result and analysis are significant for application of ZnO crystal, especially for the design of ZnO light emitter devices.