Structural analysis of the phase separation in magnetic semiconductor (Zn, Cr)Te

We have studied the structural properties of the phase separation in Zn1-xCrxTe films grown by MBE with a relatively high Cr composition x similar to 0.2. In the combined analyses using TEM and EELS, it has been revealed that the Cr-aggregated regions are composed of precipitates of the hexagonal structure, which are formed in a particular crystallographic relation with the zinc-blende (ZB) structure of the matrix that the c-plane of the hexagonal structure nearly parallel to the (1 1 1) plane of the ZB structure. In the XRD measurements, the diffraction from the hexagonal precipitates has been detected in the omega-scan. From the measurements on the series of films grown at different temperatures, it has been suggested the hexagonal precipitates were formed in a larger quantity with the increase in growth temperature. (C) 2011 Elsevier B.V. All rights reserved.