Seagate thinks "leaky" drives may lead to more capacity
Scotts Valley (CA) - According to a patent application filed by Seagate, nanotubes soaked with lubricant may lead to drastic increases in hard drive capacity. The application titled "Magnetic recording system with continuous lubrication of recording media", outlines an ingenious system where lubricant is evaporated from nanotubes and then deposited on the magnetic media of the drive.
The lubricant will be stored in millions of carbon nanotubes (CNT) held in a reservoir inside the drive chassis. According to the patent, the large surface area of the CNTs can hold a "nearly infinite reservoir of lubricant." In practical terms, the lubricant will run out after around 10 years of usage.
Future drives will Heat Assisted Magnetic Recording (HAMR) where a laser temporarily heats up an area to increase magnetic sensitivity. The heating allows drive makers to make higher capacity drives, but the lubricant does wear out.
The concept of the patent is actually quite simple. When the drive is off, the platter is coated with perfluoropolyether (PFPE). Vapor PFPE also surrounds the platter. As the drive spins, areas of the platter will get hot, which will wear out the lubricant. The vapor PFPE deposits on the platter to replace the worn out lubricant. The "condensing" vapor lowers vapor pressure which then draws out lubricant from the CNTs until the pressure is equalized.
There is no word when the technology will hit commercial shelves. Once implemented, the technology will enable storage densities of several Tbit per square inch - up from a maximum of about 170 Mbit per square inch in today's most advanced production drives.