Electrical and microstructural properties of silver thin films

Abstract

The growth, structure and electrical properties of evaporated thin silver (Ag) films have been extensively investigated over the years because it has the highest electrical conductivity among all metals. The Ag thin films have been studied by thermal evaporation on glass, mica and Teflon. The thickness of Ag films in this investigation is in the range of 10-150 nm. The electrical properties include measurement of resistivity, the temperature coefficient of resistance (TCR), and activation energy (Ea) as a function of film thickness (t) have been studied. The experimental results are analyzed in the light of Fuchs-Sondheimer (FS) and Mayadas-Shatzkes (MS) theories. The resistivity of infinitely thick Ag film and TCR are found to be 3.53 × 10-8 Ω-m and 3.73 × 10-3/°C, respectively. The mean free path of conduction electron calculated from the resistivity and TCR data are 42.8 nm and 26.28 nm, respectively. A study on the initial stages of growth of Ag films and its microstructural properties has been conducted using a Scanning Electron Microscope (SEM) for films grown on different substrates and thickness.