EPR studies of native and impurity-related defects in II–IV–V2 semiconductors

Magnetic resonance studies of native defects in Zinc germanium diphosphide (ZnGeP₂) and their energy level positions in the band gap are reviewed and first results on defects in ZnSiP₂ are presented. The contribution of the dominant native defects to the optical absorption of ZnGeP₂ crystals is revealed by photo-EPR investigations in combination with the first ODMR experiments. The EPR results published for Mn and Fe in the II–IV–V₂ chalcopyrites are summarized. The observation of some new Mn centers and the first experimental detection of antiferromagnetic Mn–Mn coupled pairs in ZnGeP₂ are presented. In addition, new results concerning Mn-induced local changes of the free parameter x_f of the chalcopyrite structure at the impurity site are discussed.