Scanning tunneling microscopy and spectroscopy of Si/SiGe(001) superlattices

Cross-sectional scanning tunneling microscopy and spectroscopy were used to study a modulation-doped Si/Si0.76Ge0.24(001) superlattice. Contrast between the Si and Si0.76Ge0.24 layers has been observed in topographic images. Features such as band-edge discontinuities and band bending arising from doping have been detected in spectroscopic measurements at a series of points across the superlattice structure.