MULTIATOMIC STEP FORMATION WITH EXCELLENT UNIFORMITY ON VICINAL (111)A GAAS-SURFACES BY METALORGANIC VAPOR-PHASE EPITAXY

Giant steps with high uniformity and continuity have been successfully formed by metalorganic vapor-phase epitaxy on GaAs(111)A vicinal surf aces for the application of quantum wire fabrication. The step height is more than 30 monoatomic layer at a growth temperature of 660 degree s C. The surface morphologies obtained from scanning electron microsco py and atomic force microscopy measurements show the straight steps on (111)A substrates misoriented toward <[(2)over bar 11]> direction wit h high uniformity. Terrace uniformity and step continuity are improved as the off-angle increases. A straight section of a step exceeding 10 mu m was obtained on 4 degrees off-substrate. Fluctuation has also be en suppressed within 1 monoatomic layer height on this vicinal substra te.