Atomic layer deposition of semiconductor oxides on electric sail tethers

his study shows that thin coating layers of semiconductor oxides, deposited by atomic layer deposition, can be successfully used to improve the performance of tethers used in space technology. Thin layers of ZnO, TiO2 and Ti-Zn mixed oxide with 25 to 100 nm thickness were considered, and compared with native Al2O3 as reference. For this purpose, morphological, optical and electrochemical characterization was performed. As a result, deposited materials show very good adhesion and conformality. Coatings act as anti-reflective layers, increasing the absorbance of tethers. The presence of TiO2 thin layers and mixed oxide improves the corrosion resistance of tethers both in dark and under UV illumination conditions. Our results show that TiO2 has the best performance for space tether application followed by the mixed oxide.