Effect of Cu Co-doping on the Magnetism of Zn0.95Co0.05O Films

doi:10.1007/s12204-012-1356-z

Abstract

Abstract: Zn0.95-xCo0.05CuxO (atomic ratio, x = 0—8%) thin films are fabricated on Si(111) substrate by reactive magnetron sputtering method. Detailed characterizations indicate that the doped Cu ions substitute the Zn2+ ions in ZnO lattice. The doped Cu ions are in +1 and +2 mixture valent state. The ferromagnetism of the Zn0.95-xCo0.05CuxO film increases gradually with the increase of the Cu+ ion concentration till x = 6%, but decreases for higher Cu concentration. Experimental results indicate that the increase of ferromagnetism is not owing to the magnetic contribution of Cu+ ions themselves, but owing to the enhancement of magnetic interaction between Co2+ ions, which suggests that p-type doping of Cu+ ions plays an important role in mediating the ferromagnetic coupling between Co ions.

Key words: Zn0.95-xCo0.05CuxO films| magnetic semiconductors|bound magnetic polaron model| co-doping

摘要： Zn0.95-xCo0.05CuxO (atomic ratio, x = 0—8%) thin films are fabricated on Si(111) substrate by reactive magnetron sputtering method. Detailed characterizations indicate that the doped Cu ions substitute the Zn2+ ions in ZnO lattice. The doped Cu ions are in +1 and +2 mixture valent state. The ferromagnetism of the Zn0.95-xCo0.05CuxO film increases gradually with the increase of the Cu+ ion concentration till x = 6%, but decreases for higher Cu concentration. Experimental results indicate that the increase of ferromagnetism is not owing to the magnetic contribution of Cu+ ions themselves, but owing to the enhancement of magnetic interaction between Co2+ ions, which suggests that p-type doping of Cu+ ions plays an important role in mediating the ferromagnetic coupling between Co ions.

关键词: Zn0.95-xCo0.05CuxO films| magnetic semiconductors|bound magnetic polaron model| co-doping

CLC Number:

O 472.5

LI Jian-jun1,2 (李建军), ZHU Jin-bo1* (朱金波), ZHANG Li-ting1 (张丽亭),LIU Yin1 (刘银), HAO Wei-chang2 (郝维昌). Effect of Cu Co-doping on the Magnetism of Zn0.95Co0.05O Films[J]. Journal of shanghai Jiaotong University (Science), 2012, 17(6): 738-742.

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