Abstract: The disclosed technology generally relates to methods of fabricating magnetic memory devices, and more particularly to methods of forming a magnetic tunnel junction (MTJ) stack. In one aspect, a method of forming the MTJ includes providing an MTJ material stack comprising a ferromagnetic material and forming thereon a protective mask layer to cover an active area of the MTJ material stack. The method additionally includes incorporating a glass-forming element into exposed portions of the ferromagnetic material. The method additionally includes at least partially amorphizing the exposed portions of the ferromagnetic material, wherein at least partially amorphizing transforms the exposed portions of the ferromagnetic material into an electrical insulator.