Preparation Of Niobium Nitride Thin Films By Magnetron Sputtering: Effect Of Power On Structural, Mechanical And Chemical Properties

Abstract

Niobium nitride (NbN) thin films have been deposited on Si (100) and stainless steel (AISI 304) substrates using Dc magnetron sputtering technique at different values of power from 100 watt to 150 watt, during deposition process; target-substrate distance has been 5 cm and at substrate temperature 100⁰C.

The depositions were carried out from Nb metal target. Scanning electron microscope (SEM) used for determined the thickness of NbN thin films, where the deposition rate has been found to increase with increasing the power.

The power effect on the crystalline quality and texture has been investigated by means of X-ray Diffraction (XRD). FCC (δ–NbN) phase has been identified and the grain size has been found to decrease with increasing the power. The composition of the films has been determined by Energy Dispersive X-ray (EDX) technique. The study shows that the microhardness of films strongly depends on the grain size, the hardness of these films increased with the increasing of power (by approximately 12%).

The results obtained indicate that the NbN films by magnetron sputtering can inhibit the aggressive action of corrosion media (0.9% NaCl solution to which the perforated trays are exposed in the sterilization stage in the serum production line) more closely compared to the substrates using electrochemical corrosion device by potentiodynamic method (Tafel curves). It was noticed that the corrosion resistance, for film NbN/(AISI 304) stainless steel, increased with increasing power during deposition process, due to decreasing grain sizes by about 8%.