A Raman spectroscopic study of the Si, Be, and C incorporation in InxGa1−xAs relaxed layers

The incorporation of high concentrations (≳1019 cm−3) of Si, Be, and C in InxGa1−xAs relaxed layers has been studied as a function of In content (x≤0.16) by Raman spectroscopy of local vibrational modes (LVM). The frequencies of the Raman peaks resulting from the convolution of several split modes shift to lower values as the In content is increased, the carbon acceptor (CAs) local mode frequency showing the strongest dependency on x. Features attributed exclusively to the influence of In on second‐neighbor sites are identified only in the Si‐doped samples. The transverse and longitudinal modes expected from the splitting of a LVM of CAs with one In first neighbor are not observed in layers with x up to 0.085. A new calibration for the BeGa, CAs, and Si‐related LVM leads to the conclusion that In increases the total electrical activation of Si and favors its incorporation on group‐III sublattice sites. In contrast, no influence of In on the Be or C doping activation has been detected. The analysis of the ...