New materials to make advanced recording technology possible

Heat-Assisted Magnetic Recording (HAMR) could provide hard drive storage densities in the TB/in^2 range, as compared to today’s GB/in^2 capability. HAMR operates by heating the disk with a laser, which momentarily changes the storage medium’s magnetic coercivity, allowing data to be written to the disk at a higher density than conventional methods. 

Hard disks are currently coated with a protective outer layer of hydrogenated amorphous carbon, which degrades above 150C. Finding a suitable disk coating material that can survive high temperatures without interfering with magnetic recording and data retrieval will be a key enabling technology for HAMR.

Researchers at the University of Pennsylvania have developed a new coating that could provide several advantages for HAMR-enabled hard drives. In this process, a thin (2nm) layer of Silicon Oxide-doped diamond-like carbon (SiO DLC) is deposited onto the disk as a replacement for the amorphous carbon layer. This material is highly temperature resistant and can withstand the temperatures required for HAMR without degrading. This coating is stable up to at least 300C, making it well-suited for HAMR.

• Uniform deposition demonstrated on a large (300 mm) surface in the laboratory
• High temperature resistance up to 300C
• Improved performance as compared to conventional amorphous carbon coatings