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 surfaces for the application of quantum wire fabrication. The step height is more than 30 monoatomic layer at a growth temperature of 660 degrees C. The surface morphologies obtained from scanning electron microscopy and atomic force microscopy measurements show the straight steps on (111)A substrates misoriented toward <[(2)over bar 11]> direction with 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 been suppressed within 1 monoatomic layer height on this vicinal substrate.