| Summary: | A ternary Cr<sub>2</sub>AlB<sub>2</sub> phase was deposited as a film using magnetron sputtering. Its anisotropic structure displays both structural and chemical similarities with the nanolaminated MAX phases (M<sub>n+1</sub>AX<sub>n</sub> (n = 1–3) where M usually is an early transition metal, A is typically an element in group 13–14 and X is C or N), and can be described as CrB slabs separated by layers of Al. Combinatorial sputtering was used to optimise the sputtering process parameters for films with the Cr<sub>2</sub>AlB<sub>2</sub> composition. The influences of substrate, temperature and composition were studied using X-ray diffraction, X-ray photoelectron spectroscopy and electron microscopy. Films deposited at room temperature were X-ray amorphous but crystalline films could be deposited on MgO substrates at 680 °C using a composite Al-B, Cr and Al targets. X-ray diffraction analyses showed that the phase composition and texture of the films was strongly dependent on the chemical composition. Films with several phases or with a single Cr<sub>2</sub>AlB<sub>2</sub> phase could be deposited, but an additional Al target was required to compensate for a loss of Al at the high deposition temperatures used in this study. The microstructure evolution during film growth was strongly dependent on composition, with a change in texture in Al-rich films from a preferred [<sup>010</sup>] orientation to a [<sup>100</sup>]/[<sup>001</sup>] orientation. A model based on Al desorption from the surface of the growing grains is proposed to explain the texture variations.
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