Co-Doped ZnO Dilute Magnetic Semiconductor
Authors: Prater, John T.; Ramachandran, Shivaraman; Tiwari, Ashutosh; Narayan, Jagdish
Source: Journal of Electronic Materials, Volume 35, Number 5, May 2006 , pp. 852-856(5)
Abstract:This paper reports on recent findings in the Co-doped ZnO system where as-deposited samples with n-type semiconductor properties display magnetic ordering above room temperature. Detailed atomic scale structural characterization has eliminated clustering and second-phase formation as the source of the magnetic behavior. Upon high-temperature annealing in oxygen, the samples become insulating and the magnetization drops. This suggests that the observed magnetic behavior of the oxide is directly related to the presence of intrinsic defects, notably oxygen vacancies and Zn interstitials. These defects are believed to mediate exchange coupling of the Co spins through electron doping of the matrix, and perhaps also the formation of bound magnetic polarons.
Document Type: Research Article
Publication date: 2006-05-01