Microtribology between Single Crystals of Silicon

Abstract

Microtribology of silicon single crystals is one of the key technologies from the viewpoint of reliability of practical application to microelectromechanical systems (MEMS). In this study, a silicon single crystal (100) wafer was scratched by a silicon single crystal tip under a very small loading force in an atomic force microscope. The scratched area of the wafer surface was elevated with respect to the original, unscratched surface, forming a terrace. The height of the terrace depended on the number of scratch, but did not depend on the loading force. The terrace was a silicon single crystal which was coherent with the silicon single crystal wafer, in spite of the different crystal orientations between the silicon single crystal wafer and the silicon single crystal tip. The friction force of the scratching was very small and did not depend on the loading force. Based on these results, it was concluded that the contact area between the silicon single crystal wafer and the silicon single crystal tip was molten by heat caused by the friction of scratching. Wear debris was an amorphous SiO 2 .