Overview of Phase-Change Electrical Probe Memory

Abstract

Phase-change electrical probe memory has recently attained considerable attention owing to its profound potential for next-generation mass and archival storage devices. To encourage more talented researchers to enter this field and thereby advance this technology, this paper first introduces approaches to induce the phase transformation of chalcogenide alloy by probe tip, considered as the root of phase-change electrical probe memory. Subsequently the design rule of an optimized architecture of phase-change electrical probe memory is proposed based on a previously developed electrothermal and phase kinetic model, followed by a summary of the state-of-the-art phase-change electrical probe memory and an outlook for its future prospects.

Surface Study of Ge2Sb2Te5-Based Electrical Probe Memory for Educational Archival Storage

“…As a result, rms roughness implemented in our model include both aforementioned experimentally reported values and some arbitrarily chosen values to more comprehensively assess its influence on the write and readout performances of the phase-change electrical probe memory. The write model of phase-change electrical probe memory consists of the Laplace equation for the electrical process, the heat conduction equation for the thermal process, and the rate equation for the phase-transformation process respectively, giving rise to [10]:…”

“…As the write/read current is almost bounded inside a region directly underneath the probe, the device resolution drastically relies on the size of the probe tip, and using a probe with small diameter can therefore increase the storage density remarkably [10]. Additionally, the vigorous development of phase-change random access memory (PCRAM) during last two decades has demonstrated the several merits of phase-change materials (represented by Ge 2 Sb 2 Te 5 , usually abbreviated as GST) including fast switching speed, low power consumption, and small feature size [11]- [13].…”

Applications of Phase Change Materials in Electrical Regime From Conventional Storage Memory to Novel Neuromorphic Computing

“…More efforts have therefore been devoted to the optimization of the media stack including capping layer, phase-change layer and bottom layer. Bottom layer that acts as the bottom electrode to collect current was reportedly found to have a slight impact on the write and readout performances of phase-change probe memory [97], [98]. However, the bottom layer is commonly desired to have large electrical conductivity and low thermal conductivity to provide adequate current density and reduce heat dissipation towards substrate [97].…”

“…Bottom layer that acts as the bottom electrode to collect current was reportedly found to have a slight impact on the write and readout performances of phase-change probe memory [97], [98]. However, the bottom layer is commonly desired to have large electrical conductivity and low thermal conductivity to provide adequate current density and reduce heat dissipation towards substrate [97]. Several bottom electrodes with different compositions such as diamond-like carbon (DLC) [99], metal [100], and TiN [101], [102], have been implemented in the past.…”

Switchable Phase Transition from Crystalline to Amorphous States of Cadmium Sulfate Octahydrate Single Crystals by Shock Waves

“…[17] Reversible phase change (from amorphous to crystalline) materials are always given prime importance as they have a wide array of technological applications such as switchable dielectrics, thermal energy storage devices, piezoelectrics, ferroelectrics, pyroelectric as well as nonlinear optical channel waveguides as compared to the phase changing materials of forward or backward phase transitions. [18][19][20] Moreover, in the past few decades, there are lots of research going on towards the understanding of the reversible phase change occurring in materials that are either crystalline-crystalline-crystalline (CCC) [14][15][16][17] or crystalline-amorphous-crystalline (CAC) [18][19][20] achieved by various methods such as synthetic techniques and static high-pressure methods. Very recently, shock-wave-induced reversible phase changes such as crystallographic phase changes (K 2 SO 4 ) and magnetic phase changes (Co 3 O 4 , ZnFe 2 O 4, and MnO 2 ) have been observed by our group.…”