Structure and Microstructure of Binary Nitride TiN Thin Films Deposited by DC Reactive Sputtering

Abstract

Titanium nitride (TiN) thin films were deposited on to unheated silicon (100) and stainless steel substrates by home-made direct current (DC) reactive magnetron sputtering method at a deposition of 60 min in an Ar-N2 gas mixture. The effects of sputtering power on structure and microstructure of these films have been studied. The films were analyzed by X-ray diffraction (XRD), Atomic Force Microscope (AFM) and Field-Emission Scanning Electron Microscope (FE-SEM). The films colors were influenced by sputtering parameter which altered from green purple to light gold and dark gold, respectively. By XRD, the polycrystalline structure of the as-deposited films was face center cubic (fcc) of TiN structure with (111), (200), (220), and (311), planes. The increasing of sputtering power transformed film from amorphous phase to crystal phase with crystal size were enhanced from 21.9 nm to 39.8 nm. The AFM scans revealed that sputtering power significantly affected surface morphologies and thicknesses of the TiN films. With increase in sputtering power, the roughness and films thickness were increased from 0.5 nm to 25.1 nm and 331 nm to 1113 μm, respectively. The microstructure combined with cross-section analysis FE-SEM revealed that the grain refinement with columnar structure were obtained for the film deposited at sputtering power of 270 W.