Perpendicular-current exchange-biased spin valve structures with micron-size superconducting top contacts

We describe an optical-lithography-based sample preparation technique for m easuring the current-perpendicular-to-plane (CPP) magnetoresistance with mi cron-size current-contact areas on top of magnetic multilayer samples of mi llimeter in-plane size. We use Permalloy and Co91Fe9 exchange bias spin val ves to show that the CPP specific magnetoresistance (area times change in r esistance) is independent of the contact area size A over the range 4 mum(2 )less than or equal toA less than or equal to1 mm(2). (C) 2001 American Ins titute of Physics.