Methods of Manufacturing Three-Dimensional Arrays with MTJ Devices Including a Free Magnetic Trench Layer and a Planar Reference Magnetic Layer

A method of manufacturing a Magnetic Tunnel junction (MTJ) device, comprising:

• forming a planar reference magnetic layer on a planar non-magnetic insulator layer;
• forming a trench through the planar reference magnetic layer;
• forming a tunnel insulator layer on sidewalls of the trench;
• forming a free magnetic layer on the tunnel insulator layer within the trench;
• removing one or more portions of the tunnel insulator layer and free magnetic layer to separate the tunnel insulator layer and free magnetic layer into a plurality of portions;
• forming one or more insulator blocks between the separated portions of the tunnel insulator layer and free magnetic layer;
• and
• forming a plurality of conductive cores on the portions of the free magnetic layer separated by the one or more insulator blocks in the trench.

A method of manufacturing a memory cell array comprising:

• forming an array of selectors on a substrate;
• forming a plurality of word lines on the substrate, the plurality of word lines being coupled to the array of selectors in respective rows;
• forming a plurality of source lines on the substrate, the plurality of source lines being coupled to the array of selectors in respective columns;
• depositing one or more planar non-magnetic insulator layers on the array of selectors;
• forming a plurality of Magnetic Tunnel Junction (MTJ) cells over the one or more non-magnetic insulator layers;
• and
• forming one or more bit lines over the plurality of MTJ cells.