Back heating effect of media hot spot at nanoscale head-disk interface

Heat-assisted magnetic recording (HAMR) is one of prospective high density recording technologies in current hard disk industry due to its theoretical potential. In this paper, we develop a new heat transfer model which enables us to predict near field thermal conduction and radiation across head-disk interface accurately. This new model, together with an Ansys finite element (FE) model for an integrated HAMR slider and an optical absorption model for temperature profile of media hot spot, is then used to solve for temperature rise and thermal protrusion on the slider body. Our simulation studies show that larger hot spot and smaller head-disk spacing will increase the temperature and thermal protrusion on the slider's head components. When thermal radiation effect is further considered, this increment in temperature and protrusion becomes more significant; especially at very small gap below 1 nm. Therefore, the back heating effect from media hot spot should be addressed carefully for improving the reliability of HAMR head-disk interface.