No 1, Vol. 3, 2002 
 

PHASE TRANSFORMATIONS IN SILICON UNDER CONTACT LOADING

V. Domnich and Y. Gogotsi*

Drexel University, Department of Materials Engineering,
Philadelphia, PA 19104, USA

Abstract

This review provides an analysis of the state of the art in the emerging research area of high-pressure surface science of silicon. Phase transformations and amorphization that occur in silicon under contact loading, such as indentation with hard indenters, scratching or machining, will be described. Contact loading is one of the most common mechanical impacts that materials can experience during processing or use. Examples are dicing, slicing, grinding, polishing and other machining operations. This kind of loading may be accommodated by such competing processes as dislocation-induced plasticity, microfracture, mechanochemical interactions with the environment and/or counterbody, and changes in the material's structure (phase transformations). The former ones have been studied by mechanical engineers and tribologists, but the processes of phase transformations at the sharp contact have only been investigated for a very few materials (silicon is one of them) and further research is necessary. One of the reasons for the lack of information may be the fact that the problem is at the interface between at least three scientific fields, that is, materials science, mechanics, and solid state physics. Thus, an interdisciplinary approach is required to solve this problem and understand how and why a hydrostatic or shear stress in the two-body contact can drive phase transformations in materials.

full paper (pdf, 1088 Kb)