Lubricant Depletion under Various Laser Heating Conditions in Heat Assisted Magnetic Recording (HAMR)

摘要

Heat assisted magnetic recording (HAMR) is expected to increase the storage areal density to more than 1 Tb/in~2 in hard disk drives (HDDs). In this technology, a laser is used to heat the magnetic media to the Curie point (～400-600 °C) during the writing process. The lubricant on the top of a magnetic disk could evaporate and be depleted under the laser heating. The change of the lubricant can lead to instability of the flying slider and failure of the head-disk interface (HDI). In this study, a HAMR test stage is developed to study the lubricant thermal behavior. Various heating conditions are controlled for the study of the lubricant thermal depletion. The effects of laser heating repetitions and power levels on the lubricant depletion are investigated experimentally. The lubricant reflow behavior is discussed as well.