Abstract
Saturation magnetostriction (λs) of CoFeBAl Ox Co magnetic tunnel junctions (MTJs) has been measured. There are three kinds of MTJs in this study, i.e., glassCoFeB (tA) Al Ox (δ to) Co (tB) with tA + tB =150 Å; tA =100, 75, and 50 Å; and δ to =0-30 Å. When plotting λs as a function of δ to, the curve is concave up. We also investigated the compositional distribution of Fe, Al, and O across the tunneling part of the CoFeB (75 Å) Al Ox Co (75 Å) junction. Based on these results, we propose a model to describe how the total λs is affected by the CoFeBAl Ox and Al Ox Co interfaces. © 2006 American Institute of Physics.