High Power Impulse Magnetron Sputtering of In₂O₃/Sn Cold Sprayed Composite Target

High Power Impulse Magnetron Sputtering (HiPIMS) was used for deposition of indium tin oxide (ITO) transparent thin films at low substrate temperature. A hybrid-type composite target was self-prepared by low-pressure cold spraying process. Prior to spraying In₂O₃ and oxidized Sn powders were mixed in a volume ratio of 3:1. Composite In₂O₃/Sn coating had a mean thickness of 900 µm. HiPIMS process was performed in various mixtures of Ar:O₂: (i) 100:0 vol.%, (ii) 90:10 vol.%, (iii) 75:25 vol.%, (iv) 50:50 vol.%, and (v) 0:100 vol.%. Oxygen rich atmosphere was necessary to oxidize tin atoms. Self-design, simple high voltage power switch capable of charging the 20 µF capacitor bank from external high voltage power supply worked as a power supply for an unbalanced magnetron source. ITO thin films with thickness in the range of 30-40 nm were obtained after 300 deposition pulses of 900 V and deposition time of 900 s. The highest transmission of 88% at λ = 550 nm provided 0:100 vol. % Ar:O₂ mixture, together with the lowest resistivity of 0.03 Ω·cm.