data storage capabilities promise for high-density PCM data storage products [10,11]. Moreover, based on their all-round characteristics including high speed, high density and low power non-volatile operations [12] PCM is considered as a strong contender for 'Universal Memory' [13,14].Significant efforts have been devoted to identify materials with unique combination of properties such as fast phase trans itions that govern high speed programming, large property contrast between the two phases and thermally stable amorphous phase [2,15]. Compounds located in GeTe-Sb 2 Te 3 pseudo-binary line (Family-I) of the Ge-Sb-Te phase diagram have shown unique property portfolio suitable for data storage