Inverted spin valves for magnetic heads and sensors

Inverted spin valves (Si substrate/Ta/X/Fe50Mn50/Ni80Fe20/Cu/Ni80Fe20/Ta with X=Cu or Ni80Fe20) have been investigated by transmission electron microscopy and magnetoresistance measurements. The newly proposed Ni80Fe20 buffer layer provides a significantly increased magnetoresistance ratio compared to the usual Cu buffer. This makes it possible to use inverted spin valves instead of conventional spin valves in magnetic heads and sensors, offering reduced corrosion sensitivity and a higher GMR ratio. First test structures for tape heads have been fabricated and evaluated.