화학공학소재연구정보센터
Applied Surface Science, Vol.252, No.24, 8482-8486, 2006
Transitions of microstructure and photoluminescence properties of the Ge/ZnO multilayer films in certain annealing temperature region
The Ge/ZnO multilayer films have been prepared by rf magnetron sputtering. The effects of annealing on the microstructure and photoluminescence properties of the multilayers have been investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectrometry and photoluminescence (PL) spectrometry. The investigation of structural properties indicates that Zn2GeO4 has been formed with (2 2 0) texture and Zn deficiency from Ge/ZnO multilayer films in the process of annealing. However, lower Zn/Ge ratio can be improved by annealing. The annealed multilayers show three main emission bands at 532, 700, and 761 nm, which originate from the transition between oxygen vacancy (V-0*) and Zn vacancies (V-Zn), the radiative recombination of quantum-confined excitons (QCE) in Ge nanocrystals, and the optical transition in the GeO color centers, respectively. Finally, the fabrication of thin film Zn2GeO4 from Ge/ZnO multilayer films by annealing at low temperature provides another approach to prepare the green-emitting oxide phosphor film:Zn2GeO4:Mn. (c) 2005 Elsevier B.V. All rights reserved.