Structural, chemical and electrochemical studies of bismuth oxide thin films growth via Unbalanced Magnetron Sputtering
By Orozco-Hern
Published in Surfaces and Interfaces
Surfaces and Interfaces
2020
Abstract
A study on the physical, chemical and electrochemical (properties) behavior of bismuth oxide thin films is presented in this work. Thin films were grown on 316 L stainless steel substrates via Unbalanced Magnetron Sputtering (UMS) in reactive phase, varying the DC power applied to the target between 20 and 80 W with 10 W step, keeping the gases flow constant at 9 sccm and the Ar/O2 ratio at 80:20. X-ray diffraction analysis was carried out for the structural characterization, showing that the crystallinity of the films strongly depends on the power of the discharge. The elemental chemical composition was determined using the Rutherford Backscattering (RBS) technique, making it possible to observe that the films were composed by a mixture of crystalline bismuth and possibly amorphous bismuth oxide. With this technique, the thickness of the coatings was measured, observing that this parameter increased from 200 to 700 nm as power values increased. Finally, the electrochemical analysis showed that corrosive behavior depends on the sample growth conditions and coatings thickness.