Influence of In doping on electro-optical properties of ZnO films

Abstract

Thin metallic films of Zn and In/Zn were deposited onto glass substrates by thermal evaporation under vacuum. The metallic films were submitted to a thermal oxidation in air, at 623 K, for different oxidation times (30-90 min), in order to be oxidized. Structural and morphological analyses (X-ray diffraction, transmission electron microscopy and scanning electron microscopy) revealed that the obtained undoped and In-doped ZnO thin films possess a polycrystalline structure. Transmission spectra were recorded in spectral domain from 280 to 1400 nm. The influence of In doping and oxidation parameters as well, on the optical parameters (transmittance, optical bandgap, Urbach energy) were analysed. It was clearly evidenced that by In doping, the optical properties of ZnO films were improved. The temperature dependence of electrical conductivity was studied using surface-type cells with Ag electrodes. The obtained results indicate that In-doped ZnO films exhibit an enhancement of electrical conductivity with few orders of magnitude when compared with non-doped ones.

The effect of Pb doping on the characteristic properties of spin coated ZnO thin films: Wrinkle structures

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Investigation of characteristics of ZnO:Ga nanocrystalline thin films with varying dopant content

“…(11) is considered, ln(α) vs hυ plot should be linear and the Urbach energy values can be obtained from the slope of this plot (Fig. 4) [53]. Calculated E U values are presented in Table 2.…”

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“…There is no indication of any other dopants in the ZnO film . doping, which may be due to Burstein-Moss effect [15,16]. The doping increases the carrier concentration, when the Zn 2+ ions are replaced by Sn 4+ ions, which may shift the Fermi level [17] leading to widening of bandgap and increase in transmission.…”