Near infrared dark-field microscopy with video for studying defects in III-V compound materials

Abstract
A system is described using near infrared dark-field microscopy (DFM) for the analysis of defects in III-V compound materials. The microscope uses a halogen bulb light source and a silicon vidicon camera detector. High-contrast images of defects are shown as bright detail on a dark background. For the same view, DFM gives image detail contrast as high as 100%, compared with 25% in bright-field illumination. Digital image processing is used for improving the presentation of results. Individual point scatterers of 0.5-3 mu m in size, interpreted as being due to microprecipitates decorating dislocations, are shown in various substrates of GaAs.