Comparative study of sputter-deposited SnO₂ films doped with antimony or tantalum

SnO₂ films doped with antimony or tantalum were sputter-deposited for comparison, using an identical set of parameters. The influence of dopant concentration and choice of deposition parameters such as substrate temperature on the optoelectronic properties, especially film resistivity, were determined. Comparative analysis shows that tantalum doping yields lower film resistivity, probably due to an increased inhibiting influence of grain boundary scattering in the case of antimony doping. Sputter-deposited tantalum-doped films with lower than previously achieved resistivity 5.4×10-4 Ωcm, carrier density 4.5×1020 cm-3, and mobility 25.7cm2Vs-1 are reported, while maintaining optical transmittance above 85% at a film thickness 400 nm. Ta/Sb co-doped thin films were synthesized for the first time, achieving similar results. Comparison of resistivity values achievable by doping sputter-deposited tin oxide films with antimony (blue) or tantalum (red) as a function of dopant concentration.