Self-Aligned Two-Step Process for Flux Enhancement in Magnetoresistive Sensors
Original Publication Date: 1983-Dec-01
Included in the Prior Art Database: 2005-Feb-07
A magnetic yoke for enhancing the performance of a magnetoresistive sensor is formed by a low temperature deposition process to minimize Barkenhausen noise. By an appropriate sequence of mask etching, components of the yoke structure and the magnetoresistive element are formed with great precision. - A thick (e.g., 3,000 ) layer 10 of nickel-iron alloy is first vacuum-deposited onto substrate 11 while the substrate is maintained at about 100ŒC. - Through the use of an appropriate mask, an opening 12 is formed in the layer 10 by sputter etching. - A thin (350 ) nickel-iron layer 13 is vacuum-deposited over the entire surface while maintaining the substrate 11 at about 250ŒC and while applying a magnetic field of about 60 0e along axis 12 to set the easy axis of the magnetoresistive element.