Conduction band structure of GexSi1−x using spatially resolved electron energy-loss scattering

Publisher Website
Google Scholar
Abstract
Transmission electron energy‐loss spectroscopy has been used to follow the positions of the Δ1 and L1 conduction‐band minima, and the L3 saddle point, as a function of Ge content in GexSi1−x (x=0–0.95) alloys. By analyzing the shape of the Si 2p→conduction‐band (CB) spectra we find that L3 and Δ1 shift largely together, as the band‐structure compatibility relations predict. L1 shifts rapidly downwards with respect to Δ1 as the Ge content increases. Measurements were carried out in a scanning transmission electron microscope at a spatial resolution of better than 2 nm. Based on these results, this technique can be used to identify the composition of thin GexSi1−x alloys with a precision of better than 5%.