화학공학소재연구정보센터
Applied Surface Science, Vol.253, No.4, 1953-1959, 2006
Work function of sol-gel indium tin oxide (ITO) films on glass
Indium tin oxide (ITO) films (physical thickness, 250-560 +/- 25 nm) were deposited on soda lime silica (SLS) glass and silica layer coated (similar to 200 nm physical thickness) SLS glass substrates by sol-gel technique using alcohol based precursors containing different In:Sn atomic percentages, namely, 90:10, 70:30, 50:50, 30:70. Cubic phase of In2O3 was observed up to 50 at.% Sn while cassiterite SnO2 phase was observed for 70 at.% Sn. Work function of the films was evaluated from inelastic secondary electron cutoff of ultraviolet photoelectron spectroscopy (UPS) energy distribution curve (EDC) obtained under two experimental conditions (i) as-introduced (ii) after the cleaning of the surface by sputtering. Elemental distribution and the presence of oxygen containing contaminant and carbon contaminant of the samples were done by XPS analysis under same conditions. The work function changed little due to the presence of surface contaminants. It was in the range, 3.9-4.2 eV (+/- 0.1 eV). (c) 2006 Elsevier B.V. All rights reserved.