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We report that magnetron sputtering can be applied to synthesize MAX-phase films of several systems including Ti–Si–C, Ti–Ge–C, Ti–Al–C, and Ti–Al–N. In particular, epitaxial films of the known phases Ti₃SiC₂, Ti₃GeC₂, Ti₂GeC, Ti₃AlC₂, Ti₂AlC, and Ti₂AlN as well as the newly discovered thin film phases Ti₄SiC₃, Ti₄GeC₃ and intergrown structures can be deposited at 900–1000 °C on Al₂O₃(0001) and MgO(111) pre-seeded with TiC or Ti(Al)N. From XTEM and AFM we suggest a growth and nucleation model where MAX-phase nucleation is initiated at surface steps or facets on the seed layer and followed by lateral growth. Differences between the growth behavior of the systems with respect to phase distribution and phase stabilities are discussed. Characterization of mechanical properties for Ti_n+1Si–C_n films with nanoindentation show decreased hardness from about 25 to 15 GPa upon penetration of the …