Plasma-Assisted Synthesis and Physical Chemical Characterization of Titanium Nitride Films

摘要

TiN films synthesized by radio-frequency plasma-assisted chemical vapor deposition onto M2 tool steel were investigated. TiCl sub 4 with NH sub 3 or with H sub 2 and N sub 2 were used 0.2 to 1.0 torr. Film composition, structure, and mechanical properties were strongly influenced by chlorine concentration within the films and at the film-substrate interfaces. Chlorine concentration in the films decreased with increasing deposition temperature. A transition from an amorphous zone one morphology, to a fine-grained zone T morphology, to a highly crystalline zone two morphology with (200) preferred orientation was observed with increasing deposition temperature. Films formed at temperatures lower than 400 deg C exhibited poor mechanical properties. At 400 deg C and above, film adhesion was influenced by initial deposition conditions. Films formed from TiCl sub 4 and NH sub 3 had low scratch adhesion test critical loads, with fracture occurring at the interface. Auger analysis of scratch tracks created in vacuum revealed a high interfacial chlorine content. In contrast, films synthesized with H sub 2 and N sub 2 exhibited higher scratch adhesion test critical loads, with fracture within the film. Auger depth profilng revealed no chlorine accumulation at the interfaces of H sub 2 -N sub 2 -based films. Early film growth was accompanied by TiN islands. A plasma was essential for TiN synthesis from TiCl sub 4 , H sub 2 , and N sub 2 . The chlorine concentrations of titanium carbonitride films, synthesized in a plasma with the addition of CH sub 4 showed greater variation at fixed deposition temperature than those of pure nitride films. The use of an organometallic source, titanium tetrakis dimethylamide, resulted in the formation of carbonitride powders. 140 refs., 88 figs. (ERA citation 13:030611)