Mechanism of texture formation in MgO buffer layers using ion-beam assisted laser deposition

Biaxially textured MgO films have been grown using ion-beam assisted pulsed laser deposition. Above 250 degreesC a cube texture with a (1 1 0) direction parallel to the ion beam is observed in films thinner than 10 nm at ion incidence angles between 35degrees and 55degrees. The in-plane alignment determined using RHEED analysis was better than 21degrees. A strongly anisotropic sputter rate is responsible for this oriented nucleation. During further growth the nucleation texture changes in such a way that the (1 00 ) direction becomes parallel to the ion beam. This change can also be explained by the anisotropic sputter rate of MgO found in sputtering experiments on single crystals selecting grains with a (1 0 0) direction parallel to the ion beam during growth. (C) 2002 Elsvier Science B.V. All rights reserved.