Defect transformation under growth of submonolayer oxides on silicon surfaces at low temperatures

The defect transformation under growth of submonolayer oxides on silicon surfaces is studied in situ on reconstructed Si(100)-2 x 1 and Si(111)-7 x 7 surfaces and on hydrogenated Si surfaces of Si nanocrystallites. The methods of the quenching of the photoluminescence of bulk c-Si due to surface recombination and of the infrared free carriers absorption in mesoporous Si are used. It is shown that dangling bonds at Si-Si dimers are not recombination active. Non-radiative surface defects are generated during the earliest stages of oxidation. The generation of hole traps is tightly related to an increase of physisorbed H2O at hydrogenated Si surfaces during the native oxidation. (C) 2001 Elsevier Science B.V. All rights reserved.