Local thicknesses of a GaAs epitaxial layer grown on a mesa stripe by semiparallel Ga and As4molecular beams have been found to be proportional to cos&fgr;Ga, where &fgr;Gais a local incident angle of the Ga beam to a local crystal growing surface. Submicron‐thick three‐dimensional GaAs‐Ga1−xAlxAs multilayers have been grown self‐aligningly on corrugated structures with a 8‐&mgr;m period. The layer thicknesses and AlAs compositions (x) are also interpreted by the local incident angles of Ga and Al beams, while evidence of atom diffusion is revealed.