Overview of Phase-Change Chalcogenide Nonvolatile Memory Technology

Abstract

Phase-change nonvolatile semiconductor memory technology is based on an electrically initiated, reversible rapid amorphous-to-crystalline phase-change process in multicomponent chalcogenide alloy materials similar to those used in rewriteable optical disks. Long cycle life, low programming energy, and excellent scaling characteristics are advantages that make phase-change semiconductor memory a promising candidate to replace flash memory in future applications. Phase-change technology is being commercialized by a number of semiconductor manufacturers. Fundamental processes in phase-change semiconductor memory devices, device performance characteristics, and progress toward commercialization of the technology are reviewed.

Storage-class memory: The next storage system technology

“…In their article in this journal issue, Burr et al [2] provide an overview of SCM candidate device technologies and then compare them in terms of their potential for scaling to ultrahigh areal density [2]. Of the many SCM technologies described in their paper, the one that seems to be in the best position to replace the current flash technology and serve as SCM in the next decade is phasechange memory (PCM) [15,16]. For the remainder of this paper, all numerical estimates are based on the use of PCM.…”

Nanostructure–property relations for phase‐change random access memory (PCRAM) line cells

“…Since the flap does not restrict the width of the amorphous mark as the line is doing, the mark develops a mushroom shape with a dome inside the flap. Note that it is a 2D mushroom and not a 3D mushroom shape that occurs in the Ovonics-type phasechange memory [1,2].…”

“…Even though Flash memory exceeds the expectations that were foreseen in the past, it is expected in the near future that further downscaling is no longer possible [1][2][3]. PCRAM on the other hand is scalable with the next generations of lithography, requires less lithographic steps, has a higher (over)writing speed, improved endurance (cyclability) and requires less program energy [1][2][3].…”

Observation of high pressure o-GeTe phase at ambient pressure in Si-Te-Ge glasses

“…1 Further, tellurium alloys are used for optical data storage in commercial rewritable phase change media. In literature, germanium-telluride glasses belong to IV-VI group have received considerable attention due to their technological applications.…”