Raman scattering has been used to characterize Ge1−xMnx (0.01 < x < 0.051) epilayers grown by MBE on Ge substrates. Ge–Mn clustering corresponding to a Ge3Mn5 hexagonal structure was observed at higher Mn concentration in cross-sectional TEM. Micro-Raman spectroscopy was employed to obtain information about the clusters and host material. Two Raman lines were observed significantly below the bulk Ge value suggesting the epilayers had Ge–Mn alloying and/or strain. A saturation in the intensity of the lower energy Raman peak with Mn-fraction suggested there was a maximum Mn incorporation rate of ∼1% with additional Mn accommodated by clustering. Evidence for increased cluster density at higher Mn-fractions were observed in the spatial Raman maps.
Raman measurements of Ge1-xMnx epilayers
PINTO, Nicola
2008-01-01
Abstract
Raman scattering has been used to characterize Ge1−xMnx (0.01 < x < 0.051) epilayers grown by MBE on Ge substrates. Ge–Mn clustering corresponding to a Ge3Mn5 hexagonal structure was observed at higher Mn concentration in cross-sectional TEM. Micro-Raman spectroscopy was employed to obtain information about the clusters and host material. Two Raman lines were observed significantly below the bulk Ge value suggesting the epilayers had Ge–Mn alloying and/or strain. A saturation in the intensity of the lower energy Raman peak with Mn-fraction suggested there was a maximum Mn incorporation rate of ∼1% with additional Mn accommodated by clustering. Evidence for increased cluster density at higher Mn-fractions were observed in the spatial Raman maps.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
