In situ infrared study of chemical state of Si surface in etching solution

We have ‘‘in situ’’ investigated the chemistry of Si(100) surfaces during immersion in hydrofluoric acid (HF) solution, using infrared spectroscopy in the multiple internal reflection geometry. During immersion in dilute HF solution, hydrogen termination is not completed and hydrogen-associated Si fluorides may be generated on the surface. We demonstrate that water rinse following treatment with HF solution leads to the complete hydrogen termination of Si surfaces.