Fabrication and Characterisation of Diluted Magnetic Semiconductors Thin Films Using Ion Beams

Abstract:

The intrinsic n-type (II-VI) semiconductor ZnO may become ferromagnetic at room temperature, by small additions of magnetic ions, resulting in what is called a Diluted Magnetic Semiconductors (DMS). The potential application of DMS in spintronic devices of is driving the research effort to dope magnetic elements into this semiconductors with a depth distribution as uniform as possible. The doping levels and the depth distribution of dopants are critical parameters for the magnetic properties of this material and the possible clustering of dopants can play a significant negative role in its macroscopic magnetic properties. Thin ZnO (0001) films of between 100nm and 500nm, grown on c-Al₂O₃ by MOCVD were implanted with Co, Eu and Co+Eu by ion irradiation at low energies. In order to improve the depth distribution of dopants, the ion implantation was carried out through a number of appropriately chosen range foils. The results show an increase in the level of dopant homogeneity throughout the entire thickness of the film, and a ferromagnetic behavior above room temperature for Zn_0.96Co_0.04O, Zn_0.96Eu_0.04O and Zn_0.92Co_0.04Eu_0.04O.

• Periodical: Materials Science Forum (Volumes 706-709)
• Pages: 2869-2873
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.706-709.2869
• Online since: January 2012
• Authors: M. Ionescu, P. Photongkam, R. Siegele, A. Deslantes, S. Li, D.D. Cohen
• Keywords: Diluted Magnetic Semiconductor (DMS), Ion Beam Doping, ZnO Thin Film

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