FORMATION OF INAS QUANTUM DOTS BY METALORGANIC MOLECULAR-BEAM EPITAXYUSING TRISDIMETHYLAMINOARSENIC AND BISDIMETHYLAMINOARSENICCHLORIDE

InAs quantum dot structures having no wetting layer are fabricated on GaAs substrates by MOMBE (metalorganic molecular beam epitaxy). InAs d ot structures with wetting layers are first formed by Stranski-Krastan ov growth mode with TMIn (trimethylindium) and TDMAAs (trisdimethylami noarsenic). The InAs wetting layers are subsequently removed by in sit u etching with BDMAAsCl (bisdimethylaminoarsenicchloride). The etching rate of InAs increases exponentially with temperature and linearly wi th BDMAAsCl flow rate, and is much higher than that of GaAs, which mak es it possible to selectively etch the InAs wetting layers. InAs quant um dot structures having Mn atoms inside are also fabricated by the pr edeposition of Mn atoms acting as nuclei for the enhanced decompositio n of TMIn molecules. (C) 1998 Elsevier Science B.V. All rights reserve d.