Fabrication of TiN thin film by shadow-masked pulsed laser deposition

Abstract

A shadow-masked pulsed laser deposition (SPLD) technique has been used to fabricate TiN thin film on a silicon substrate. By interposing a chosen mask of the appropriate size and location between the laser-induced plasma plume and the substrate, it was possible to vary the quality and smoothness of the resultant film. While all the films produced by shadow-masking represent a marked improvement over the conventional pulsed laser deposition (PLD) technique, it was also observed that the masking caused a considerable reduction in the deposition rate. The nearer the shadow mask was to the substrate the greater the film quality produced but the lesser the deposition rate. From X-ray diffraction analyses of the thin films it was found that an important reason for the surface defects of those films produced by the unmasked PLD method was the existence of multiple orientations of the different crystal domains. The SPLD technique reduced the occurrence of such multiple orientations and improved crystal alignment direction by preventing lumpy clusters originating from the laser ablation from reaching the substrate.