STRUCTURAL AND OPTICAL STUDIES OF CDTE ZNTE SUPERLATTICES WITH ULTRATHIN ZNTE LAYERS/

Spatially selective introduction of ultrathin ZnTe layers (1 to 3 mono layers) into CdTe allows the study of special superlattice structure, corresponding to a monomolecular plane-host crystal system. Particular attention is given to the strain state control of the inserted ZnTe m onolayer. High resolution electron microscopy is used to measure the l ocal lattice distortion: the method yields the location and the total amount of Zn per period, and the results are compared with X-ray diffr action data. Optical properties of these superlattices are also presen ted. All results show the ability to control ultrathin pseudomorphic l ayers of ZnTc within CdTe, with limited Zn segregation, and of high cr ystalline and optical quality. In addition, they can be fitted within the framework of elasticity theory for the structural data, and of a f inite quantum well model for the optical ones, even in the ultimate li mit of only one nominal ZnTe monolayer.