Tunable Optical and Structural Properties of MgxZn1−xO Films Prepared by In Situ Atomic Layer Doping Technique

Abstract

Magnesium zinc oxide (MgxZn1−xO) thin films with tunable optical and structural properties have been prepared by in-situ atomic layer doping technique. The linear dependence of the Mg content on the Mg atomic layer doping percentage indicates this in-situ atomic layer doping is a precisely controlled technique for the Mg incorporation into ZnO. X-ray characterization reveals that solubility limit of MgO in the MgxZn1−xO films is approximately x = 0.1. Photoluminescence (PL) measurement shows the near-band-edge emission of MgxZn1−xO films shifts from 378 nm to 346 nm with an increase of the Mg content. The temperature dependent PL spectroscopy shows that the activation energy of thermal quenching process increases from 17 meV in pure ZnO to 48 meV in Mg0.1Zn0.9O films, indicating that thermal quenching is suppressed by the Mg incorporation. The optically-pumped stimulated emission at λ ∼ 356 nm was observed from the Mg0.1Zn0.9O film, manifesting the high optical quality of the MgxZn1−xO films grown by the in-situ atomic layer doping technique.