In situ atomic force microscopic observation of growth of islands of organic contaminants on an H–Si(1 1 1) surface

Atomic forcemicroscopic (AFM) images of anH–Si(1 1 1) surface having the atomically flat structureweremeasured in a normal laboratory atmosphere. By monitoring time series changes in the AFM images, we found that islands grow on the surface. A comparison of the growth of islands with changes in Fourier-transfer IR(FTIR) spectra showed that the islands are formed by organic contaminants adsorbed fromthe air in the laboratory. Starting chiefly fromthe step sites, the islands extend to cover thewhole surface in about 2 h. Following the adsorption of the organic contaminants, oxidation of the Si surface proceeds gradually. Although the growth rate was slightly slower, similar growth of islands was observed in a plastic bag filled with nitrogen gas with high purity. # 2004 Elsevier B.V. All rights reserved