Control of porosity and optical properties of slanted columnar Ni thin films

Abstract In this work we deposited nickel thin films by Glancing Angle Deposition at two different angles (65° and 85°) onto glass substrates. The structure of the films, thicknesses between 50 and 200 nm, was studied by scanning electron microscopy, atomic force microscopy and X-ray diffraction, while the chemical properties were analyzed using X-ray photoelectron spectroscopy. According to the obtained results it can be seen that the deposition angle has influence on porosity, crystallinity and surface roughness. Optical properties were investigated by spectroscopic ellipsometry and electrical properties were measured by four point probe. Spectroscopic ellipsometry revealed that the refractive index and extinction coefficient varied with thickness and deposition angle, which can be correlated with changes in microstructure and porosity of Ni films. The observed variations in resistivity could be attributed to the changes in the width of the columns, as well as to the amount of oxide present in the samples.