Thin oxides and their interface, formed by dry oxidation of hydrogen-enrich
ed (100)Si and (111)Si substrates via r.f. hydrogen plasma exposure at 850
degrees C. are studied by multiple-angle spectroscopic ellipsometry in the
range 280-632.8 nm. Comparison with the standard oxidation of RCA cleaned S
i shows that on plasma treated Si the initial oxide growth rate is higher a
nd a thicker interface is formed with a different composition. Various proc
esses involving hydrogen are suggested to be responsible for changes in int
erface properties. (C) 2000 Elsevier Science B.V. All rights reserved.