A review of position annihilation spectroscopy as a defect and microstructural probe of thin films

Abstract

A general review is given on position annihilation spectroscopy (PAS) applied to the characterization of the defect and microstructural properties of thin films. Applications of PAS to thin films are presented as a function of processing parameters such as deposition rate, substrate preparation, reactive gas pressure and post-annealing. PAS can be used to investigate type and density of the defects in thin films, the atomic structure of defects such as vacancy complexes, extended defects such as dislocations and phase inhomogeneities. Through the application of “slow” PAS, a technique controlling the implantation depth of positrons into a thin film, the thickness and defect structure of individual layers within multilayered thin film structures may be determined, in addition to disorder, structure and impurity states at interfaces.