STRUCTURE OF THE SI(011)-(16X2) SURFACE AND HYDROGEN DESORPTION-KINETICS INVESTIGATED USING TEMPERATURE-PROGRAMMED DESORPTION

D-2 temperature-programmed desorption (TPD) was used to probe the stru cture of the Si(011)-(16 x 2) surface. Deuterium was adsorbed at 200 d egrees C to coverages theta(D) ranging up to complete saturation (appr oximately 1.1 ML) and the sample heated at 5 degrees C s(-1). TPD spec tra exhibited three second-order desorption peaks labelled beta(2), be ta(1) and beta(1) centered at 430, 520 and 550 degrees C. Of the prop osed models for the Si(011)-(16 x 2) reconstruction, the present TPD r esults as a function of theta(D) provide support for the adatom/dimer model with the beta(2) peak assigned to D-2 desorption from the dihydr ide phase, while the beta(1) and beta(1) peaks arise from adatom and surface-atom monohydride phases. (C) 1997 Elsevier Science B.V.