Ordering of germanium clusters during epitaxy on patterned silicon substrates

Semiconductor surfaces have been patterned by a novel method based on the g rowth of metal clusters directly on the surface as masks for subsequent low energy ion beam modification. During subsequent wet etching, well-defined mesa structures were obtained. When these are overgrown with 5 to 50 monola yers of germanium, field emission scanning electron microscopy shows growth of crystallographically ordered Ge clusters not only on the substrate betw een the mesas but also on the slopes of the mesas. The latter clusters show a distinct orientational correlation, and ordering in size and nearest nei ghbor distance.