The results of experimental studies of processes of the radiation defect formation under ion implantation of narrow-gap CdxHg1-xTe solid solutions (MCT) are presented. The processes of formation of structural damages of the crystal and their effect on the electrophysical properties of ion-implanted bulk crystals and ptype heteroepitaxial structures grown by liquid-phase and molecular-beam epitaxy are considered. The results on the spatial distribution of implanted boron atoms and radiation donor centers in these materials are presented as a function of the mass, dose, and energy of ions being implanted and the implantation temperature. The processes and models of the formation of n+–n-–p-structures during boron ion implantation in p-type MCT and their experimental proof are considered.