METHOD FOR ENCAPSULATING MAGNETIC TUNNEL JUNCTION, METHOD FOR FORMING MAGNETIC DEVICE, AND STRUCTURE OF MAGNETIC TUNNEL JUNCTION

摘要

PPROBLEM TO BE SOLVED: To provide a structure of magnetic tunnel junction which is subjected to heat treatment without an increase in the tunnel resistance value and a drop of the MTJ breakdown voltage, and also to provide a method for encapsulating magnetic tunnel junction for providing the same, and a method for forming a magnetic device comprising the same. PSOLUTION: An MTJ lamination structure is obtained by sequentially, selectively etching the region other than the element region by ion milling etc., after laminating an anti-ferromagnetic layer 12, a pinned layer 13, an insulating tunnel layer 14, a free layer 15, and a cap layer 16 in this order. Next, after forming a first encapsulating layer 31 in an oxygen-free atmosphere, a second encapsulating layer 32 is formed in an oxygen atmosphere. By laminating double the encapsulating layer 31 not including additionally embedded oxygen and the second encapsulating layer abundant in oxygen, and encapsulating an MTJ lamination structure, the MTJ junction is insulation separated from the outside without fail, and also the safety of the tunnel resistance value is secured even if subjected to a thermal treatment process in the post stage. PCOPYRIGHT: (C)2007,JPO&INPIT