Multi-scale study of Ti3SiC2 thin film growth mechanisms obtained by magnetron sputtering

Abstract

Abstract In the present work we focus on the mechanisms involved in Ti3SiC2 MAX phase thin-film formation and on the impact of stoichiometry and thickness/element quantity correlation. TiAlx thin-films, with x = 0 -- 2 , 100–300\u2009nm thick, were deposited by magnetron sputtering on a SiC-4H (0001) substrate. Samples were annealed at 1000\u2009∘C for 30\xa0min and analyzed by XRD, AFM, SEM and TEM. The MAX phase Ti3SiC2 was formed at 1000\u2009∘C in accordance with thermodynamic considerations. Moreover, an epitaxial relation between the film and the substrate occurred as follows (0001)MAX//(0001)SiC and [ 12 1 ¯ 0 ] M A X / / [ 12 1 ¯ 0 ] SiC due to the formation of an earlier TiC phase by species interdiffusion. The catalytic role of Al has been demonstrated and explained by the formation of Ti2AlC as precursor for Ti3AlC2 and for Ti3SiC2. Finally, second phases and continuity of films have been controlled by x and thickness factors. Indeed, the MAX phase film continuity is obtained for Al richer films, whereas the purest MAX phase have been synthesized for the thinnest layer of TiAlx deposited.