Positron annihilation, X-ray and ESR studies of iron ion implanted crystals of potassium bromide and quartz

Abstract

The association of electron spin resonance. X-ray diffraction and positron annihilation techniques has been applied to the study of radiation-induced defects in iron implanted single crystals of KBr and quartz with the implant dose of 5 × 10¹⁵ ions/cm². Two kinds of defect creation processes due to the ion bombardment are found in these crystals. In the ionic crystal KBr, the F-centers that already existed in the sample before implantation aggregate in the halogen sublattice by electronic processes during ion implantation, and a new crystal structure is formed either due to lattice dilatation caused by F-center aggregation and metallic ion precipitates, or due to the formation of an Fe⁺³ compound. In quartz, only F-type centers (i.e., E¹₁ centers) are created in the oxygen sublattice through nuclear collision cascades by ion implantation.