Comparison of Defect Images and Density Between Synchrotron Section Topography and Infrared Light Scattering Microscopy in Heat‐Treated Czochralski Silicon Crystals

Abstract

Density of crystal defects in Czochralski silicon wafers, which had been subjected to various heat treatments, are studied by two different kinds of methods, i.e. synchrotron section topography and infrared light scattering microscopy (LSM). A comparison of the results shows that both these techniques reveal the existence and density of crystal defects. The defect densities given by LSM are larger than those given by section topography, because of its capability to reveal small oxygen precipitates, which are smaller than the resolution of the topographs. It is shown that the LSM technique is a powerful tool to investigate small oxygen precipitates even in samples whose topographs show only the Pendellösung fringe pattern characteristic of a perfect crystal. It is also determined that the volume of the smallest identifiable oxygen precipitates with LSM is through comparative observations by means of transmission electron microscopy.