Ferromagnetism and Conductivity in Hydrogen Irradiated Co-Doped ZnO Thin Films

• DOI: 10.1021/acsami.6b04203
• Publication Date: 2016-04-28T19:43:53Z
• Authors: A. Di Trolio; P. Alippi; E. M. Bauer; G. Ciatto; M. H. Chu; G. Varvaro; A. Polimeni; M. Capizzi; M. Valentini; F. Bobba; C. Di Giorgio; A. Amore Bonapasta
• Keywords: 0103 physical sciences; Co-doped ZnO thin films; conductivity; ferromagnetism; hydrogen incorporation; Materials Science (all); conductivity; hydrogen incorporation; ferromagnetism; Co-doped ZnO thin films; 01 natural sciences

Impressive changes in the transport and ferromagnetic properties of Co-doped ZnO thin films have been obtained by postgrowth hydrogen irradiation at temperatures 400 °C. Hydrogen incorporation increases saturation magnetization one order magnitude (up to ∼1.50 μB/Co) carrier density mobility about a factor two. In addition magnetic characterization, structural hydrogenated ZnO:Co investigated Hall effect, local probe conductivity measurements, micro-Raman, X-ray absorption spectroscopy. Particular care has given detection Co oxides metal nanophases, whose influence on increase can be excluded ground achieved results. The enhancement ferromagnetism is directly related dose H introduced samples. On contrary, despite shallow donor character atoms, n not dose. These apparently contradictory effects are fully accounted for mechanism based theoretical model involving Co-VO (Co-O vacancy) pairs.