Greater than 14 Gb/in/sup 2/ spin valve heads

We have designed and fabricated dual spin valve heads with synthetically pinned layers. They have excellent sensitivity. The read-back waveform has a small asymmetry and that is also insensitive to the bias current. The read gap length is of 0.14 /spl mu/m and the write gap length is of 0.2 /spl mu/m. The read heads have a nominal magnetic trackwidth of 0.5 /spl mu/m and a nominal write magnetic trackwidth of 0.8 /spl mu/m. The write heads were conventional inductive heads with their pole geometry defined by focused ion beam (FIB) technology. The dual spin valve heads have achieved an areal read/write density as high as 14.5 Gb/in/sup 2/ at a data transfer rate of 23/spl sim/24 MB/sec. The sensitivity of the readers is as high as 3.6 mVp-p//spl mu/m. The bit aspect ratio is as high as 14.