Abstract
Al doped ZnO films have been prepared using different Ar:O2 ratios and annealing conditions on glass substrates by dc
reactive magnetron co sputte ring. The results of magnetic measurements show that different oxygen partial pressures and
annealing temperatures have great influence on the magnetism of doped ZnO thin films. The fact that only the films prepared
at an Ar:O2 ratio of 1:1 and annealed at 200 oC in vacuum show clear room temperature ferromagnetism which disappears
after anneal ed at 500 o C in vacuum indicates that the ferromagnetism may be related to internal lattice stress. These
ferromagnetic films have been annealed at 200 oC in air subsequently and show lower coercivity and enhanced saturation
magnetization, which may be attributed to the annealing in air causing more interstitial Al atoms to convert into substitutional
Al ions, and consequently i ncreasing the charge transfer between the Al and the ZnO matrix , leading to increased
magnetism..
Keywords
Diluted magnetic semiconductor, Oxygen partial pressure, Anneal, Ferromagnetism.
Citation
YUNKAI QI, SHUMIN YANG, JIANJUN GU, GUOLIANG ZHAO, HUIYUAN SUN, Influence of oxygen partial pressure and annealing on magnetic properties of Al doped ZnO thin films, Optoelectronics and Advanced Materials - Rapid Communications, 7, 5-6, May-June 2013, pp.420-424 (2013).
Submitted at: May 6, 2012
Accepted at: June 12, 2013