Phase-Change Memory by GeSbTe Electrodeposition in Crossbar Arrays

Abstract

Phase-change memory is an emerging type of nonvolatile memory that shows a strong presence in the data-storage market. This technology has also recently attracted significant research interest in the development of non-Von Neumann computing architectures such as in-memory and neuromorphic computing. Research in these areas has been primarily motivated by the scalability potential of phase-change materials in crossbar architectures and their compatibility with industrial nanofabrication processes. In this work, we have developed crossbar phase-change memory arrays through the electrodeposition of GeSbTe (GST). We show that GST can be electrodeposited in nanofabricated TiN crossbar arrays using a scalable process. Various characterization techniques, such as atomic force microscopy (AFM), transmission electron microscopy (TEM), and energy-dispersive X-ray (EDX) were used to study electrodeposited materials in these arrays. Phase-switching tests of electrodeposited materials have shown a resistance switching ratio of 2 orders of magnitude with an endurance of around 80 cycles. Demonstrating crossbar phase-change memories via electrodeposition paves the way toward using this technique for developing scalable memory arrays involving electrodeposited materials for passive selectors and phase-switching devices.

Electrodeposition of GeSbTe-Based Resistive Switching Memory in Crossbar Arrays

“…A Cr (10 nm)/Au (200 nm) global contact at the top quarter of the substrate was also patterned to connect each individual word line with a potentiostat. The detailed fabrication process can be found in our previous work. , A Pt/Ir (90%:10%) disk was employed as the counter electrode and an Ag/AgCl wire (0.1 M [N n Bu 4 ]Cl in anhydrous CH 2 Cl 2 ) was used as the reference electrode.…”

“…46,48 The process offers good control over the composition across the GeSbTe ternary phase diagram. 73 These device-quality thinfilms have demonstrated both phase-change switching 46,74 and ECM-based resistive switching when integrated with active Ag electrodes. 57 This work will present, for the first time, the resistive switching of the electrodeposited chalcogenide GeSbTe material in a crossbar architecture.…”

“…Electrodeposition is a well-established deposition method in the electronic industry that offers a low-cost and fast alternative solution for chalcogenide deposition. , As a “bottom-up” growth method, it is a site-selective technique, which can be extremely beneficial for deposition in nanopatterned substrates and three-dimensional nanostructures. , Our group has previously reported the electrodeposition of amorphous ternary GeSbTe thin films from a single, highly tunable, non-aqueous electrolyte. , The process offers good control over the composition across the GeSbTe ternary phase diagram . These device-quality thin-films have demonstrated both phase-change switching , and ECM-based resistive switching when integrated with active Ag electrodes …”

Impact of Thermal Boundary Resistance on Thermoelectric Effects of the Blade-Type Phase-Change Random Access Memory Device

“…Owing to this attractive trait, PCMs, particularly represented by Ge 2 Sb 2 Te 5 alloy (GST), have been commonly adopted for various commercialized phase-change memories such as rewritable digital versatile disc (DVD) (Pieterson et al, 2004), Blu-ray disc (Aoki, 2003), and PCRAM (Kwon et al, 2015). Additionally, their ability to dynamically modulate either the electric resistance or the optical reflectivity renders these devices with an exciting memristive behavior, thereby triggering their new applications including in-memory computing (Noori et al, 2021) and neuromorphic computing (Wang et al, 2017a).…”

High Driving Current Selector Based on As-Implanted HfO2 Thin Film for 3D Phase Change Memory

“…High-density nonvolatile memories are desirable for next generation memories to face the limit of the scale-down for emerging 3D stacking applications. − Among the nonvolatile memories, phase change memory (PCM) has received a great attention for its low power consumption, fast switching speed, and good scalability. , The breakthrough of high-density cross-array structure will support the development of 3D stacking technology. Intel’s 3D XPoint technology has achieved 3D stacking PCM by using a high driving capability threshold switching selector, which can reduce the sneak current in the cross-point array structure. − So far, the 3D stacking of PCM is mainly limited by the size and performances of the selector devices.…”