Chemical Treatment Effects of Si Surfaces in NH4OH:H2O2:H2O Solutions Studied by Spectroscopic Ellipsometry

Abstract
Chemically treated Si surfaces in 1NH4OH:XH2O2:5H2O (X=0 and 1) solutions at 80°C have been studied using spectroscopic ellipsometry (SE). The SE data clearly indicate that the X=0 solution results in surface roughening while the X=1 solution, in surface chemical oxidation. It is found that chemical oxidation occurs immediately upon immersing the sample in the X=1 solution. The thickness of the oxide is also found to show a saturated value of ∼11 Å against immersion time t.