The magnetoresistance (MR) of (Co/Cr)(70) superlattice with hcp-Co lay
ers and bcc-Cr layers on both MgO and Al2O3 substrates with Mo as a bu
ffer layer, and the anisotropy magnetoresistance (AMR) of the single-c
rystal hcp-Co, fcc-Co, as well as the CoCr alloy thin films have been
studied at 10 K and 295 K, respectively. The MR of Co/Cr multilayers h
as been observed to increase by a factor of 3.8 with replacing its sub
stract MgO(100) by Al2O3(1 (1) over bar 02) only. The AMR of Co films
has been found to decrease rapidly by the buffer layer as well as the
alloying effect between Co and Cr.