MULTI-SHEETS IN0.25GA0.75AS QUANTUM DOTS GROWN BY MIGRATION-ENHANCED EPITAXY

Self-organized multi-sheets quantum dots were grown by migration-enhan ced epitaxy. The dots were studied by atomic force microscopy (AFM), c ross-section transmission electron microscopy (XTEM) and photoluminesc ence (PL). The AFM and PL show that the dot's size increases as the sh eet number increases, while the density decreases with the increase of the sheet number. This implies that the vertical alignment is not pos sible to be complete. This can also be seen from the XTEM images. The ten-sheet's dots of 22 monolayer (ML) In0.25Ga0.75As have strong room temperature PL. (C) 1998 Elsevier Science B.V. All rights reserved.