Near-infrared emission in Er:ZnO thin films with embedded Si nanoparticles synthesized by ion implantation

Abstract

Er-doped ZnO thin films on a SiO _2 /Si substrate were fabricated by radio frequency magnetron sputtering, in which embedded Si nanoparticles (NPs) were formed by ion implantation and subsequent thermal annealing. The effects of Si NPs on the Er photoluminescence (PL) at 1.54 μ m were investigated. In addition to the typical emission at 1.54 μ m from Er ^3+ , a new 1.16- μ m emission peak was also observed after a thermal treatment. Further annealing resulted in shift of emission intensity between the 1.16- and 1.54- μ m luminescence features. The observed Si nanoparticles (NPs) were ∼4 nm in diameter. The formation of new components Zn _2 SiO _4 and Er _2 Si _2 O _7 was also presented in this study. The 1.16- μ m luminescence is attributed to the Si NPs, and the suppression of Si NPs related emission is caused by consumption of Si in the formation of Er silicate and zinc silicide and the energy transfer between Si NPs and Er ^3+ . The intensity of Er ^3+ related 1.54- μ m PL can be modulated by the Si NPs fabricated by implantation and optimizing the annealing condition.

Keywords

• silicon nanoparticles
• ion implantation
• photoluminescence
• zinc oxide
• thin film