Optimization of the Electrical Properties of Sn-Doped Indium Tin Oxide Films on Three-Dimensionally Structured Surfaces

We studied the effect of excessive Sn doping on the physical properties of indium tin oxide (ITO) films prepared on flat and three-dimensional (3D) glass substrates.Bilayers of pure Sn and ITO containing In 2 O 3 and SnO 2 in a weight ratio of 90:10 (10 wt.%) were prepared using radiofrequency sputtering under base pressures of 0.5 10 -6 to 3.0 10 -6 Torr.The Sn doping of ITO was performed via in-situ post-annealing at 400 C for 30 min.The sheet resistances (R ) of Sn-doped ITO films were one-tenth of those of undoped samples.The Sn doping of ITO conducted at a base pressure below 0.6 10 -6 Torr in a sputter chamber was crucial for obtaining a low sheet resistance of less than 6.0 /.The best result was R = 4.9 observed for the Sn (2.0 nm)/ITO (400 nm) sample grown on the 3D substrate.This sample maintained a high light transmittance of 81 % for = 380 -780 nm.