Hitachi breakthrough promises 4TB drives by 2011
Monday, October 15th, 2007Hitachi announced today that it has developed the world’s smallest hard drive read heads, and that it expects the new technique to eventually quadruple hard drive size within four years.
The company’s new technology is called current-perpendicular-to-the-plane giant magneto resistive, or CPP-GMR. Current hard drives use tunneling magnetoresistance, or TMR, which allows drive heads to read data on tracks that are 70nm apart. Areal density at that point is approximately 200Gb per square inch. Increasing that density means laying data tracks closer to each other, which in turn requires a smaller read head. As a read head shrinks, however, electrical resistance and electrical noise both increase. According to Hitachi, researchers have predicted that attempting to increase areal density past 500Gb per square inch using TMR technology will be difficult, at best