Point Defect Characterization of Zn- and Cd-Based Semiconductors Using Positron Annihilation Techniques

A study of point defects in II-VI compound semiconductors was undertaken and has revealed that open volume defects are present in a wide variety of these samples. Zn-based binary compounds contain primarily neutral divacancy defects in concentrations in the mid 1016 cm−3. CdTe samples contain neutral monovacancy sized defect complexes in the high 1016 cm−3 range. When a small fraction of Zn or Se is alloyed into CdTe the defect profile changes dramatically to one dominated by divacancy sized defects at roughly half the original concentration.