DISORDERED REGIONS IN CRYSTALLINE SILICON AT HIGH TEMPERATURES.

Self-diffusion is the process by which host atoms migrate from one atomic site to another. The coefficient of self-diffusion is usually measured by using radioactive tracer host atoms. In general, self-diffusion is mediated by thermally created intrinsic defects, such as vacancies, self-interstitials, etc. These defects are created at surfaces, interfaces, voids, dislocations, and other extended defects, and migrate through the crystal. In this paper, we will review the arguments that have been advanced in support of the existence of amorphous regions in high-temperature Si. We will then review the recent theoretical results which provide a simple and systematic interpretation of the data without the need to invoke amorphous regions. Finally, we discuss the implications of these results concerning the possible existence of amorphous regions.