Fundamental understanding of vapor lubrication in hard disk drive

It is proposed to overcome lube depletion problem in future hard disk drives by using vapor lubrication. The lube film formation process on disk surface in vapor lubrication is studied theoretically based on fundamental adsorption and desorption theories. The controlling parameters of lube film thickness and film formation time are identified. It is found that the lube film thickness is controlled mainly by lube vapor pressure and molecular weight. The film formation time can be shortened by using low molecular weight lube and high temperature lube vapor.