Journal of the Korean Physical Society

pISSN 0374-4884 eISSN 1976-8524
Qrcode

Article

Cross-Disciplinary Physics and Related Areas of Science and Technology

J. Korean Phy. Soc. 2011; 59(5): 3093-3096

Published online November 15, 2011     https://doi.org/10.3938/jkps.59.3093

Copyright © The Korean Physical Society.

Effects of Post-deposition Annealing Temperature on the Structure and Photoluminescence of Zinc Germanate Thin Films Doped with Manganese

Kyung Ho Yoon, Joo Han Kim

Abstract

The effects of post-deposition annealing temperature on the structure and photoluminescence of thin film zinc germanate doped with manganese (Zn2GeO4:Mn) were systematically investigated. The Zn2GeO4:Mn films were deposited by radio frequency (RF) magnetron sputtering, followed by post-deposition annealing at temperatures of 700 – 1000 ¡É. As-deposited Zn2GeO4:Mn films had an amorphous structure with a smooth surface morphology. The Zn2GeO4:Mn films became crystalline after annealing at 700 ¡É and the crystallinity of the films was continuously improved up to 1000 ¡É. Annealed Zn2GeO4:Mn films had a polycrystalline rhombohedral structure with no preferred crystallographic orientation of the crystallites. The lattice parameters of the rhombohedral Zn2GeO4 phase were measured to be a = 14.228 ¡Ê and c = 9.525 ¡Ê. Formation of secondary phases, such as ZnGeO3 and GeO2, was observed in the films annealed at 1000 ¡É. The photoluminescence (PL) spectra of the annealed Zn2GeO4:Mn films showed broad-band emissions with a peak maximum at around 535 nm in the green range. The PL emission intensity was enhanced as the annealing temperature increased, resulting from the improvement of the crystallinity of the Zn2GeO4:Mn films. The broadening of the PL spectrum was observed for the films annealed at 1000 ¡ÆC due to the formation of secondary phases.

Keywords: Manganese-doped zinc germanate, Sputtering, Post-deposition annealing, X-ray diffraction