Tailoring Transient-Amorphous States: Towards Fast and Power-Efficient Phase-Change Memory and Neuromorphic Computing

摘要

Phase-change (PC) materials have broad applications in rewritable DVD disks, non-volatile electronic memories, reconfigurable electronics, and more recently, in the area of neuromorphic computing by virtue of their accumulative nature of the amorphous-to-crystalline phase transition (ACT) in PC materials, which allows biological-like read/write operations. PC memory (PCM) devices utilize both fast phase transitions between the amorphous (a-) and crystalline (c-) states of PC materials, and accompanying large electrical-resistance contrast, offering feasible intriguing applications in fastonvola-tileanoscale built-in information storage, particularly for their ability to scale down to nanometer length scales. However, the overall operation speeds of PCM devices, along with their corresponding power consumption, are intrinsically limited, in particular, owing to the ACT being much slower than the amor-phization process. Moreover, much still remains to be done due to the contradictory nature of increasing the ACT speed while at the same time extending the amorphous-state data-retention properties of PC materials.