ROLE OF THE SUBSTRATE DEOXIDATION PROCESS IN THE GROWTH OF STRAINED INAS INP HETEROSTRUCTURES/

We have investigated the role of the arsenic flux used during the subs trate deoxidation process in the MBE (molecular beam epitaxy) growth o f strained InAs/InP heterostructures. Two different experiments were p erformed: (i) thermal cleaning of the InP wafer under an As flux at di fferent exposure times and (ii) the growth of very thin InAs layers (3 -9 ML). The samples grown were characterized by Raman spectroscopy and selected area X-ray photoelectron spectroscopy. The results obtained demonstrated the formation of an InAsxP1-x sublayer at the interface o f the InAs/InP system. The annealing of InP under an As flux promotes not only As --> P substitution on the surface, but also the subsequent diffusion of As atoms into the deeper subsurface region of InP.