X-RAY PHOTOELECTRON-SPECTROSCOPY AND OPTICAL REFLECTIVITY STUDIES OF SI SURFACES PREPARED BY CHEMICAL ETCHING

Complementary X-ray photoelectron spectroscopy and optical reflectivit y studies of crystalline Si(111) surfaces prepared by two different we t chemical etching processes were performed. These included aqueous HF solution etch or diluted CP-4 bath. Optical reflectivity spectra of S i surfaces, measured in the range 3.7-11 eV, were found strongly depen dent on the applied etching process. Analysis of the core level X-ray photoelectron spectroscopy data has shown similarity of the surface st ructure, irrespectively of the etching procedure. Finally, comparison of optical reflectivity and valence band X-ray photoelectron spectra r evealed a qualitative correlation between them indicating dominant inf luence of the bulk (here, the subsurface region containing polishing-i nduced defects) in the case studied. This paper is the first one which presents correlations between optical reflectivity and X-ray photoele ctron spectroscopy data for Si and thus illustrates a bulk sensitivity of both techniques considered.