Signal generation mechanisms in scanning-electron acoustic microscopy of ionic crystals

Abstract

MgO crystals have been studied by scanning‐electron acoustic microscopy under different experimental conditions. Contrast mechanisms in imaging are discussed and compared. The experimental results obtained by earthing or nonearthing the specimen‐transducer interface suggest the existence of a signal generation mechanism that is related to the ionic nature of these kind of crystals. Electron‐acoustic microscopy appears then to be a useful tool for the characterization of ionic materials