Measurement of Valence Band Offset in Strained GexSi1−x/Si Heterojunctions

Abstract
The valence band discontinuity ΔEV in the coherently strained GexSi1−x/Si heterostruc-ture is determined using I-V-T measurement. The electrical measurements of the band discontinuity of the pseudomorphic layers are difficult due to the thin layer imposed by the strain. Recently, low temperature growth of thick layer (>100 nm) of coherently strained GexSi1−x on Si has been achieved and thus made it possible for an accurate electrical measurement of band offset. The results obtained are in good agreement with the theoretical calculations by pseudopotential method.