Ti 3 Si C 2 thin films were synthesized by magnetron sputtering from Ti3SiC2 and Ti targets. Sputtering from a Ti3SiC2 target alone resulted in films with a C content of ∼50at.% or more, due to gas-phase scattering processes and differences in angular and energy distributions between species ejected from the target. Addition of Ti to the deposition flux from a Ti3SiC2 target is shown to bind the excess C in TiCx intergrown with Ti3SiC2 and Ti4SiC3. Additionally, a substoichiometric TiCx buffer layer is shown to serve as a C sink and enable the growth of Ti3SiC2.

Sputter deposition from a Ti 2 AlC target was found to yield Ti-Al-C films with a composition that deviates from the target composition of 2:1:1. For increasing substrate temperature from ambient to 1000 °C, the Al content decreased from 22 at% to 5 at%, due to re-evaporation. The C content in as-deposited films was equal to or higher than the Ti content. Mass spectrometry of the plasma revealed that the Ti and Al species were essentially thermalized, while a large fraction of C with energies >4 eV was detected. Co-sputtering with Ti yielded a film stoichiometry of 2:0.8:0.9 for Ti:Al:C, which enabled growth of Ti 2 AlC. These results indicate that an additional Ti flux balances the excess C and therefore provides for more stoichiometric Ti 2 AlC synthesis conditions.

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