MAGNETORESISTIVE RANDOM ACCESS MEMORY (MRAM) DEVICE AND FABRICATION METHODS THEREOF

摘要

A method includes patterning a plurality of magnetic tunnel junction (MTJ) layers to form an MTJ cell, and forming a dielectric cap layer over a top surface and on a sidewall of the MTJ cell. The step of patterning and the step of forming the dielectric cap layer are in-situ formed in a same vacuum environment. A plasma treatment is performed on the dielectric cap layer to transform the dielectric cap layer into a treated dielectric cap layer, whereby the treated dielectric cap layer improves protection from H2O or O2, and thus degradation.