The low friction of a diamond/H-terminated Si[111] sliding system

Hydrogen-terminated Si[111] surfaces have been studied for tribological performance in sliding of a diamond slider to obtain fundamental information on contact problems between a Si memory disk and the slider. We focused on the tribological role of the atoms on the contact surfaces, and observed an extra-ordinarily low coefficient of friction: 0.003 of the relevant sliding surfaces, a coefficient as low as the sliding system of diamond/Ag monolayer/Si[111]. The observed friction reduction of 2-orders was attributed to a monolayer of hydrogen atoms terminating the Si[111] dangling bonds. The results are discussed in terms of the sliding mechanism, surface source of friction and application to reduce memory disk surface damage as the result of probable contact between slider and disk, reduction of the friction of micro-machine sliding system, and design of a sliding system in a vacuum.