The Smallest Bit: Ultimate Limits of Phase Change in Nanometer-Scale Memory Devices

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

The Smallest Bit: Ultimate Limits of Phase Change Memory William P. King and Eric Pop University of Illinois Urbana-Champaign The objective of this research is to investigate the ultimate scaling of phase change memory de-vices, below 10 nm bit size. Phase-change materials (PCM) undergo a reversible phase change accompanied by a drastic change in resistivity, induced by electric and temperature fields. PCM are prime candidates for fast, high-density memory with ultra-low power consumption. Such a technology would enable scaling of memory devices much beyond the present state of the art, represented by Flash memory or other charge storage devices like DRAM or SRAM. The ap-proach is to investigate the fundamentals of nanometer-scale electric and temperature fields that induce phase change, resulting in an understanding of the smallest data bits that can be formed in PCM. Specifically, the proposed work will perform experiments and simulations that determine the smallest addressable PCM bit using scanning probe techniques and carbon nanotubes as the electrodes. The intellectual merit of the proposed research lies in its thorough approach for achieving inde-pendent control of nanometer-scale electric fields and temperature distributions in PCM. In turn, these will allow a significant advance in understanding the behavior of materials used in phase change memory. The research will achieve broad impact by providing information about the ultimate speed, size, and longevity limits of future data storage systems. This new understanding could bring about radical changes in consumer electronics devices. The research will achieve additional broad im-pact through web-enabled communication, and personal interactions with high school teachers, undergraduate students, graduate researchers, and U.S. industry.