We present a study of morphologies - obtained by atomic force microscopy - of Be-doped humoepitaxial GaAs films grown by chemical beam epitaxy. The results show that the dopant on the surface may significantly affect the shape and size of the structures present in the film morphologies only when a large-scale roughness is observed in the initial surface for growth. Heavily doped samples (p similar to 4 x 10(19) cm(-3)) grown on these rough substrates present an anisotropic aspect ratio in the shape of the surface structures. This behavior suggests that the effect of the presence of Be atoms is different for adatom movement along different crystallographic directions on the surface. (C) 1999 Elsevier Science B.V. All rights reserved.205416713642