Structural, optical, electrical and magnetic properties of sol-gel derived Zn1-x-yCoxAlyO films

• Autorzy: Sharma M. , Mehra R. M.
• Języki publikacji: EN

Abstrakty

EN

A detailed study has been presented of optical, electrical, structural and magnetic properties of Zn1.xCoxO (0 < x ≤ 0.25) films co-doped with 1 at. % of Al. The polycrystalline films have been synthesized on Corning glass 7059 substrates by the sol-gel technique using spin coating. Highly preferential c-axis oriented films have been obtained at the annealing temperature of 600 ° C. The lattice constant d of c-axis wurtzite Zn1.x.yCoxAlyO obeys Vegard�fs law for (0 < x ≤ 0.25). The inclusion of Al in ZnO is highly beneficial for the magnetism in ZnO because it enhances the free electron density. Optical spectra measurements reveal that band gap energy exhibits a blue shift upon increasing Co concentration. A positive magnetoresistance for Co doped ZnO and negative magnetoresistance for ZnO without cobalt at 77 K has been observed. The ferromagnetic behaviour has been confirmed by measurements using superconducting quantum interference device. The coercive field and the remanence increase with increase in Co content.

Słowa kluczowe

EN

sol-gel; ZnO:Co; dilute magnetic semiconductor; hysteresis

• Wydawca: De Gruyter
• Czasopismo: Materials Science Poland
• Rocznik: 2008
• Tom: Vol. 26, No. 3
• Strony: 659--673
• Opis fizyczny: Bibliogr. 26 poz.

Twórcy

autor

Sharma M.

autor

Mehra R. M.

• Department of Electronic Science, University of Delhi, South Campus, New Delhi 110021, India,

Bibliografia

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