Direct Visualization of Instability Phenomena of Molecularly Thin Liquid Films

High-density hard disk drives (HDDs) require a very low flying height, less than 10 nm. To meet this demand, the current thickness of liquid lubricant films is molecularly thin and of the order of 1 nm. Therefore, distribution control of molecularly thin lubricant films is indispensable to high-density recording. The behavior of molecularly thin liquid films is determined by the intermolecular interaction between the liquid molecules and media surface. The instability of the molecularly thin lubricant on the disks is a big problem for the polar lubricant, which is widely used for HDDs. The instability is called dewetting, which is caused by the intermolecular interaction between the lubricant and the disk. In this paper, the dewetting of molecularly thin lubricant films on magnetic disks has been investigated by visualizing the dewetting process directly, using ellipsometric microscopy