公开(公告)号：BR9504583A

公开(公告)日：1997-05-20

申请号：BR9504583

申请日：1995-10-27

Applicant: IBM

Inventor： DOVEK MORIS MUSA ,  FONTANA ROBERT EDWARD ,  SIMONE VIRGIL ,  SPONG JACQUELINE KETNER

IPC: G01R33/09 ,  H01L43/08 ,  G01R33/06

Abstract: A magnetic field sensor (10) uses four individual magnetoresistive spin valve elements (A,B,C,D) electrically connected in a bridge circuit. The spin valve elements (A,B,C,D) are lithographically formed on the same substrate with their free layers (36) having their magnetization axes parallel to one another. An electrically conductive fixing layer is formed on the substrate but is insulated from the spin valve elements. The application of current through the fixing conductor during fabrication of the field sensor fixes the direction of magnetization of two of the pinned layers (39) to be antiparallel to the direction of magnetization of the other two pinned layers (39). The bridge circuit (10) output voltage is responsive to an external magnetic field (4) in the plane of the sensor (10). By appropriate fixing of the direction of magnetization of the pinned layers (39) during sensor (10) fabrication, and appropriate connection to the input (20,22) and output leads (24,26), the bridge circuit output voltage is a measure of either the magnetic field or field gradient.