Ionic Conductivity of AgI Film on the SiO2 Glass Substrate

The temperature dependence of ionic conductivity of the AgI films on SiO 2 glass (quartz grass) substrates has been measured for various film thickness. AgI thin films showed conductivity enhancement, and the ionic conductivity shows an increase with decreasing the thickness. The experimental results suggest the existence of the high ionic conduction region at the SiO 2 –AgI boundary. The thickness dependence of ionic conductivity of the AgI film was explained by a simple two layer model; high ionic conduction region and bulk ionic conduction region. Average ionic conductivity σ λ and thickness λ of the high ionic conduction region at 300 K were estimated as 4.65 ×10 -5 Ω -1 cm -1 and 0.28 µm, respectively.