Effect of nitrogen on the properties of sputter deposited NiFeRe films

Abstract

Bias layers for soft adjacent biased magnetoresistance (MR) heads require low coercivity, high permeability magnetic materials that can be magnetized easily by a current in the adjacent MRE layer. While the advantage of (SAL) MR heads include the ability to adjust the bias field by optimizing the bias current, a major disadvantage of this biasing technique is arises from electrical shunting due to the finite electrical resistivity of the SAL material. The introduction of N2 in the deposition ambient was found to increase the electrical resistivity, and decrease both anisotropy and saturation magnetization of the films. The increase in resistivity was attributed primarily to a decrease in the grain size of the films. As a result a series of NiFeRe films for SAL biased MR heads were deposited by radio frequency diode sputtering in a series of N2 containing ambient atmospheres.