The formation and characterization of titanium dioxide layers deposited on copper middle nano-layer

In this research, two thin layers of Cu with thicknesses of 20 ± 2 nm and 30 ± 2 nm are coated on substrates of quartz. A layer of titanium dioxide with a thickness of 300 ± 25 nm is coated on each nano layer. Also, in order to compare, a layer of titanium dioxide with a thickness of 300 ± 25 nm is coated on a substrate of quartz. All coatings are conducted using physical vapor deposition and electron beam deposition methods. The major goal is to study the impact of Cu nano layer on the surface morphology, grain size, grain boundaries, crystalline structure and phases, and some optical properties such as absorption and transmission of titanium dioxide layers. The field emission scanning electron microscope is used to analyze the surface morphology. Moreover, the crystalline structure of layers is determined using X-ray diffraction. The transmission and absorption of titanium dioxide layers are also determined using ultraviolet–visible spectroscopy. These analyses indicate that the existence of a middle nano layer of copper makes the layers’ surfaces denser and more uniform; however, it has no effect on the structure of layers’ crystalline phase and the way of transferring the layers’ crystalline phase caused by annealing. A slight increase in layers’ absorption and a small shift in absorption edge occur due to the presence of middle nano layer of copper and its thickening. Another remarkable effect that happens due to the presence of copper’s middle nano layer is the amplification and shift of absorption bands in the visible spectrum.