Giant Magneto resistive Recording Heads
Read-Rite's long-time mission has been to make significant advances in recording head technology to assist its customers, the disk drive manufacturers, in meeting the demand for storage products offering increased capacity. This continued growth in demand has come as information is increasingly digitized for a myriad of business and home purposes, and as multimedia and internet applications with ever-larger software and data files proliferate. To support this demand, Read-Rite scientists and engineers must refine and exploit leading-edge capabilities in device modeling, materials science, photolithography, vacuum deposition processes, micro-machining and numerous other advanced skills.
Anticipating future market demand for increased storage densities, in 1992 Read-Rite began investigating potential applications of the giant magnetoresistance (GMR) effect, a phenomenon involving large changes in electrical resistance that occur in specific materials sandwiched in a number of very thin layers of metals. Since that time, the Company has developed different types of recording heads based on the GMR effect. The earliest embodiment of Read-Rite's GMR technology program is a sensor structure called Spin Valve. Spin Valve-GMR recording heads are significantly more sensitive than conventional inductive and MR recording heads, allowing them to read data from computer disks and other storage media at higher densities and smaller track widths. Read-Rite produced its first Spin Valve head in November 1996. This technology-demonstration head was capable of storing 1.5 GB per 3.5 inch disk.
In April 2000, Read-Rite demonstrated another world record of 75 GB per 3.5-inch disk using an enhanced multi-layered Spin Valve head design, and it is expected that improvements in Spin Valve technology will support over 150 GB per disk. Currently Read-Rite produces Spin-Valve-GMR recording heads supporting 40 GB per 3.5-inch disk.
