The&agr;-HgI2/CdTe:Geheterostructures have been studied by cathodoluminescence (CL) in the scanning electron microscope. The&agr;-HgI2expitaxial growth was shown to cause an enhancement of the CL intensity in a layer of the substrate extending up to about 500 &mgr;m from the&agr;-HgI2/CdTe:Geinterface. CL spectra of the layer reveal the appearance of a band related to tellurium vacancies as well as the decrease of the emission attributed to defect complexes involving Ge. The data obtained indicate that Ge-impurity gettering andVTegeneration at the interface take place during&agr;-HgI2epitaxial growth. ©1997 American Institute of Physics.