Engineering grains of Ge2Sb2Te5 for realizing fast-speed, low-power, and low-drift phase-change memories with further multilevel capabilities

Phase-change memory (PCM) represents one of the best candidates for a 'universal memory'. However, its slow SET speed, high RESET power, and high resistance drift present key challenges towards this ambition. Here, grain-engineered Ge2Sb2Te5 is exploited to control the crystallization kinetics, and electrical properties of PCM. We report 120 % higher SET speeds with respect to conventional scaling. Good stability (140 °C), 30 % RESET power reduction, and 2X lower resistance drift were also achieved. A 4-state/2-bit multilevel cell was further demonstrated. This provides a route to making high-density PCM devices. © 2012 IEEE.