Formation of interfacial layers in InSb-CdTe heterostructures studied by Raman scattering

Abstract

The formation of a thin interfacial layer of indium telluride in InSb‐CdTe heterostructures has been previously suggested by soft x‐ray photoemission (SXPS) results. However, the detailed nature of this layer was difficult to interpret by SXPS. Therefore, samples being previously investigated by SXPS were studied by Raman spectroscopy. Spectra were taken of heterostructures grown by deposition of CdTe on (100) InSb substrates at room and elevated temperatures. For the room‐temperature sample the vibrational modes of CdTe and crystalline Te were detected. In the case of elevated substrate temperatures it was possible to identify the interfacial layer rich in indium and tellurium as consisting largely of In₂Te₃ using the Raman spectrum of In₂Te₃ as a fingerprint. Furthermore, the segregation of antimony was confirmed by the detection of the vibrational modes of antimony at the interface.