ORGANIZED GROWTH OF GAAS ALAS LATERAL SUPERLATTICES ON VICINAL SURFACES - WHERE ARE THE LIMITS/

We report on three issues concerning the growth of GaAs/AlAs lateral s uperlattices on vicinal surfaces to obtain quantum wires with negligib le inter-wire tunnel coupling. We show that the ledge roughness increa ses with increasing terrace length and decreases for slower growth rat es. The tilt angle of lateral superlattices is not the relevant parame ter as long as electronic properties are concerned: one has to conside r the product of the coverage error by the lateral superlattice thickn ess. The Ga flux stability is a critical parameter to be controlled. T he use of dual-filament cells improves it by a factor two compared to single-filament ones.