Nano-technologies for head-medium interface in magnetic disk storage

Nano-technologies used in head-medium interfaces for magnetic disk drives are presented. To allow for an increase in bit density, head-to-medium spacing has to be minimized. Recently, the spacing has reduced down to 40 - 50 nm. Such a ultimately small spacing could be realized by nano-technologies wherein the dimensions and physical quantities are required to be controlled to the nanometer scale. First, a law of scale analogy is introduced resulting from the history of increases in bit density. Then, the dimensions and configurations relating to the head-medium interface are described. Finally, typical nano-technologies, such as, design of a gas lubricating surface, formation of a liquid lubricant layer, manufacturing of texture and the micro-flow for lubricants are discussed.