Basics of surface reconstruction during selective area metalorganic chemical vapour-phase epitaxy of GaAs films in the stripe-type ultra-wide window

Abstract

The evolution of the surface morphology and growth steps of the GaAs film during selective area epitaxy has been studied. It has been shown that during the selective area epitaxy three regions with different growth mode and the atomic-height step orientation can be formed. A correlation between the local misorientation and the specific features of these areas has been identified. The layer surface’ local misorientation angle causes the transition between growth modes. A simulation model of the change in the growth steps’ front in the window area is proposed. It is shown that the local rotation angle of the growth steps’ front is governed by the growth rate change across the window. It was experimentally and theoretically shown that a small change in the orientation of the growth steps in the central area of the window and a rotation of the front by nearly 90°for the outermost window areas are specific features due to the symmetric mask, whereas the size of the central area decreases sharply with increasing layer thickness.