Combined use of AFM and FTIR in the analysis of the hydrogen termination of Si(100) surfaces

The preparation of hydrogen terminated Si(100) surfaces of high quality is of paramount relevance in many areas of fundamental and technological research. These surfaces must display both a sub-nanometric residual roughness and a uniform, controlled chemical termination. Both points are somewhat critical when surfaces are prepared using wetchemistry procedures. We show how a combined use of Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM) provides a rationale to surface protocols. Specifically, the effect of combined low-concentrated HF solutions, annealing, and ultrasonic cleaning on Si(100) surfaces was systematically analyzed. Through the present tutorial mini-review on FTIR and AFM of H-terminated surface, we will get to discuss about the interplay between hydrogen coverage and surface roughness at different length scales. On these bases, optimal processing conditions are found to hydrogenate Si(100) surfaces.