Re-amorphization of GeSbTe alloys not through a melt-quenching process

Abstract

Ge-Sb-Te (GST) alloys are one of the most successful chalcogenides used in rewritable optical discs and electric non-volatile memories. In these materials the structural phase transition between amorphous and crystalline states is used for recording. Here, we report that a melt-quenching method is not necessarily the only way to form a high-resistance phase. We found that amorphous-like grains with high resistance are formed in the GST crystal film by holding it at above the crystallization temperature under an external magnetic field, followed by cooling accompanied with pulse current injection. The treatment may open new route for ultra-low current switching phase change memory.