F-doped SnO2 thin films grown on flexible substrates at low temperatures by pulsed laser deposition

Fluorine-doped tin oxide (SnO2:F) films were deposited on polyethersulfone plastic substrates by pulsed laser deposition. The electrical and optical properties of the SnO2:F films were investigated as a function of deposition conditions such as substrate temperature and oxygen partial pressure during deposition. High quality SnO2:F films were achieved under an optimum oxygen pressure range (7.4–8 Pa) at relatively low growth temperatures (25–150 °C). As-deposited films exhibited low electrical resistivities of 1–7 mΩ-cm, high optical transmittance of 80–90% in the visible range, and optical band-gap energies of 3.87–3.96 eV. Atomic force microscopy measurements revealed a reduced root mean square surface roughness of the SnO2:F films compared to that of the bare substrates indicating planarization of the underlying substrate.