Investigating the Effect of Sputtering Particle Energy on the Crystal Orientation and Microstructure of NbN Thin Films

Niobium nitride (NbN) thin films are crucial materials for various applications, including superconductivity and hard coatings. However, precisely controlling their microstructure and crystal orientation during synthesis remains a challenge. This study addresses this gap by systematically investigating the effect of sputtering particle energy on NbN film properties. This research aims to elucidate the relationship between sputtering particle energy and the resulting microstructure and crystal structure of NbN thin films synthesized by reactive magnetron sputtering. NbN thin films were deposited on Si (100) substrates using reactive magnetron sputtering. The effects of sputtering power, total sputtering pressure, and nitrogen partial pressure on the films’ preferred orientation, grain size, and crystallinity were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The preferred orientation of NbN films can be controlled by sputtering parameters. Increasing sputtering power leads to a texture transition from a single -phase (111) orientation to mixed (111) and (200) orientations. Sputtering pressure influences the energy of sputtering particles and can shift the preferred orientation from mixed (111) and (200) to single-phase (200). Higher nitrogen partial pressure affects the crystallinity of NbN films, potentially introducing defects that reduce crystallinity. This study demonstrates that sputtering particle energy significantly influences the microstructure and crystal orientation of NbN thin films. Precise control of sputtering parameters enables tailored film properties, which are crucial for optimizing NbN performance in diverse technological applications.