公开(公告)号：JPH11353621A

公开(公告)日：1999-12-24

申请号：JP14418599

申请日：1999-05-25

Applicant: IBM

Inventor： FONTANA JR ROBERT E ,  PARKIN STUART STEPHEN PAPWORTH ,  CHIN FA TSUAN

IPC: G01R33/06 ,  G11B5/39

Abstract: PROBLEM TO BE SOLVED: To prevent the shunting of the sense current to a bias ferromagnetic layer and to optimize a device by determining electric resistance to current flowing perpendicularly in respective layers in a stack by the relative directions of the magnetic moments of a stationary ferromagnetic layer and detecting ferromagnetic layer when electric leads are connected to a sensing circuit. SOLUTION: The bias magnetic field in the transverse direction to a magnetic tunnel junction device (MTJ) is obtd. by the ferromagnetic bias layer 320 having a longitudinally bias region 322 near the right and left edges 180 of a detecting layer and a transverse bias region 324 along a rear surface edge 190 apart from an air bearing surface (ABS) surface. The front edge of an MTJ sensor 100 is directly arranged on the ABS or is retreated from the ABS to introduce magnetic fluxes to the retreated front edge of the sensor by using a magnetic flux guide. The transverse bias magnetic field of an adequate quantity is made possible by using an additional bias region 324 at the rear surface edge 190.