Material characterization using positron annihilation spectroscopy

Abstract

Positrons, the antimatter of electrons, can be used to detect vacancies and open spaces in materials with high sensitivity and nondestructive properties. As this technique can be applied without requirements, such as sample temperature and conductivity, it is used to study defects in metals, semiconductors, insulators, etc. The depth distribution of defects in the subsurface region can also be evaluated. This paper explains the principle of positron annihilation, introduces recent applications, and evaluates the annealing properties of vacancy-type defects and open spaces in ion-implanted semiconductors, high-k films, and SiO₂.