Impedance Spectroscopy Analysis of p Type Li Doped ZnO Thin Film Effect

Abstract:

Impedance spectroscopy technique was employed to characterize the Li_xZn_1-xO₂ (x=0.001~0.008) polycrystalline thin film. IS is shown to be an efficient method capable of detecting the contributions of the resistances of grains and grain boundaries resistance to the complex impedance of a compound, accurately estimating its electrical conductivity as well as its corresponding activation energies and conclude on its structural properties. This is demonstrated for the case of lithium segregation in the grain/grain boundary of Li_xZn_1-xO₂., we found that the activation energy decrease associated with grain-boundary conductivity reflects the onset of the segregation of excessive Li in the grain boundaries when the Li-content exceeds 0.5 mol%. For Li-content below 0.5mol% is the detection of a transition from p-type conductivity. It might be due to that the Li⁺ doped mainly in grains and no precipitation observed on the grain boundaries. So we could be process stable p type thin film for Li content below 0.5mol%.

• Periodical: Advanced Materials Research (Volumes 415-417)
• Pages: 1925-1932
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.415-417.1925
• Online since: December 2011
• Authors: Kuo Chuang Chiu, Yu Han Wu
• Keywords: DC Pulsed Sputtering, Impedance Spectroscopy, p-Type, Soft Chemical Method, ZnO Film

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