High-pressure Si phases and the mutual orientation of their structures. HRTEM studies

As a result of high-resolution transmission electron microscopy (HRTEM) studies of silicon processed in a planetary mill in the presence of diamond powder, high-pressure phases were found: Si-III, Si-IV and Si-IX; moreover, a Si-IX particle with a length of more than 10 nm was detected by TEM methods for the first time. A study of the mutual orientations of the phases obtained allowed us to propose a scheme of transformations in silicon under pressure. We have shown that the Si-IX phase can be formed from Si-IV. The orientation relationship between Si-IV and Si-IX is established.