Identification of nitrogen and zinc related vibrational modes in ZnO

Zinc oxide films with natural zinc and isotopically pure Z68n were grown by pulsed laser deposition on sapphire substrates. Prior to and after ion implantation with N2+ the samples were characterized with Raman spectroscopy. After implantation the well-known N-related vibrational modes at 273.9 and 509.5 cm−1 are observed. In the isotopically pure Z68nO samples the vibrational modes exhibit a shift of 5.4 and 1.6 cm−1 to smaller wave numbers. As a result of the experimental data the vibrational modes at 273.9 and 509.5 cm−1 are attributed to a ZnI–NO and ZnI–OI complex, respectively. This is consistent with ab initio calculations based on density functional theory.