Thin films of some Hensler alloys are ideal candidates for spin electronics since they possess a high-spin polarization at the Fermi level. We grew single crystalline layers of the Heusler alloy Cu2AlMn on MgO(1 0 0) by RF-sputtering. On sapphire a-plane we observe strongly textured (1 1 0)-growth out-of-plane and polycrystalline structure in-plane. Small angle X-ray reflectivity measurements and atomic force microscopy reveal a flat surface morphology with a roughness below 0.5 nm rms. (C) 2002 Elsevier Science B.V. All rights reserved.