Very large GMR of spin valve with specularly reflective layers

Summary form only given. Our specular spin valves fabricated by a novel technique have provided excellent head performance suitable for an ultra-high recording density. We previously used a spin valve with an oxide capping layer (a so-called single specular spin valve) for the demonstration of 56.1 Gb/in/sup 2/. The single specular spin valve was magnetically soft and its GMR value reached over 12%. However, the specularity was still low at the interface between the pinned layer and the Cu spacer. Embedding another oxide layer into the pinned layer (creating a so-called double specular spin valve), we enhanced the specularity and this led to a GMR value of over 15%. As a matter of fact, we increased the output of the read head with this double specular spin valve by more than 50% over that of the read head used in the demonstration. Therefore, we demonstrated that the head with the double specular spin valve can be used for an areal density of 106.4 Gb/in/sup 2/ in magnetic recording, with the help of advanced media and integration techniques.