Effect of Substrate Temperature on the Optical and Electrical Properties of ITO Thin Films deposited on Nb2O5/SiO2 Buffer Layer

Title & Authors
Effect of Substrate Temperature on the Optical and Electrical Properties of ITO Thin Films deposited on Nb2O5/SiO2 Buffer Layer
Joung, Yang-Hee; Kang, Seong-Jun;

Abstract
In this study, we prepared ITO thin films on $\small{Nb_2O_5/SiO_2}$ double buffer layer using DC magnetron sputtering method and investigated electrical and optical properties with various substrate temperatures (room temperature ~ $\small{400^{\circ}C}$). The resistivity showed a decreasing tendency, because crystallinity has been improved due to the enlarged grain size with increasing substrate temperature. ITO thin film deposited at $\small{400^{\circ}C}$ showed the most excellent value of resistivity and sheet resistance as $\small{3.03{\times}10^{-4}{\Omega}{\cdot}cm}$, $\small{86.6{\Omega}/sq.}$, respectively. In results of optical properties, average transmittance was increased but chromaticity ($\small{b^*}$) was decreased in visible light region (400~800nm) with increasing substrate temperature. Average transmittance and chromaticity ($\small{b^*}$) of ITO thin film deposited at $\small{400^{\circ}C}$ exhibited significantly improved results as 85.8% and 2.13 compared to 82.8% and 4.56 of the ITO thin film without buffer layer. Finally, we found that ITO thin film introduced $\small{Nb_2O_5/SiO_2}$ double buffer layer has a remarkably improved optical property such as transmittance and chromaticity due to the index matching effect.
Keywords
ITO thin film;$\small{Nb_2O_5/SiO_2}$ buffer layer;Sheet resistance;Transmittance;Chromaticity;Index matching;
Language
Korean
Cited by
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