GROWTH AND CHARACTERISTIC OF AMORPHOUS NANO-GRANULAR TeO2-V2O5-NiO THIN FILMS

作者：Hosseinzadeh Sh; Rahmati A^*; Bidadi H

来源：Surface Review and Letters, 2016, 23(2): 1550105.

DOI：10.1142/S0218625X1550105X

• Glassy thin film
• DC conductivity
• I-V characteristic
• small polaron hopping
• band tail

TeO2-V2O5-NiO thin films were deposited using thermal evaporation from 40TeO(2)-(60 - y)V2O5-yNiO (y = 0-30 mol%) target. Structural analysis of the films was identified by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The amorphous TeO2-V2O5-NiO films have nanosized clear grain structure and sharp grain boundaries. DC conductivity and current-voltage (I-V) characteristic of TeO2-V2O5-NiO thin films were measured in the temperature range of 300-423 K. As nickel oxide (NiO) content increases, the DC conductivity decreases up to two orders in value (10(-9)-10(-11) S.cm(-1)). Temperature dependence of conductivity is described using the small polaron hopping (SPH) model as well. Poole-Frenkel effect is observed at high external electric field. The optical absorption spectra of the TeO2-V2O5-NiO thin films were recorded in the wavelength range of 380-1100 nm. The absorption coefficient revealed bandgap shrinkage (3.01-2.3 eV) and band tail widening, due to an increase in NiO content. Energy dispersive X-ray spectroscopy (EDX) was used to determine elemental composition. In TeO2-V2O5-NiO thin films, the NiO content is around fifth of the initial target.

• 出版日期2016-4