Resolving Voltage–Time Dilemma Using an Atomic-Scale Lever of Subpicosecond Electron–Phonon Interaction

Abstract

Nanoelectronic memory based on trapped charge need to be small and fast, but fundamentally it faces a voltage-time dilemma because the requirement of a high-energy barrier for data retention under zero/low electrical stimuli is incompatible with the demand of a low-energy barrier for fast switching under a modest programming voltage. One solution is to embed an atomic-level lever of localized electron-phonon interaction to autonomously reconfigure trap-site's barrier in accordance to the electron-occupancy of the site. Here we demonstrate an atomically levered resistance-switching memory built on locally flexible amorphous nanometallic thin films: charge detrapping can be triggered by a mechanical force, the fastest one being a plasmonic Lorentz force induced by a nearby electron or positron bunch passing in 10(-13) s. The observation provided the first real-time evidence of an electron-phonon interaction in action, which enables nanometallic memory to turn on at a subpicosecond speed yet retain long-term memory, thus suitable for universal memory and other nanoelectron applications.

Nanofilament Dynamics in Resistance Memory: Model and Validation

“…13,14 Second, in nanometallic ReRAM, R 0 þ R s decrease with the device size, while C m increases with the overall resistance. 17,50 These nonfilamentary features are consistent with a bulk-switching mechanism. Third, nanometallic ReRAM has a rather small or vanishing R 0 , allowing its LRS resistance to asymptotically approach R E when a large |V max | is used.…”

A Material Framework for Beyond-CMOS Devices

“…When the sample size is comparable to ζ, MIT transitions can be triggered by using an electric field or ultra-violet radiation (UV) to tune ζ through the injection and extraction of electrons which decreases or increases ζ. A modest mechanical pressure can also cause an increase of ζ by removing trapped electrons [23]. Resistance switching of these materials is not field-dependent, not temperature dependent and not thermally activated such as by ionic/atomic migration or rotation or electron hopping.…”

Demonstration of Ultra-Fast Switching in Nanometallic Resistive Switching Memory Devices

“…Resistive random access memory (ReRAM) offers a competitive solution to future digital memory, given its superior properties such as long data retention, nanosecond speed, high endurance, multibit capability, and flexible scalability [1,2]. Extensive studies have been conducted to explore the resistive switching speed, which intends to answer the question: how fast "1" can be converted to "0" [3][4][5][6][7][8]. Researchers found that, in ion-migration system, such switching speed is strongly correlated with applied voltage.…”

“…In this sense, intrinsic switching speed of electronic devices should exceed that of ionic devices. A subpicosecond electronic switching has been demonstrated in [7].…”

“…Such ReRAMs exhibit outstanding device properties such as long retention and endurance [17], low power [10], and multilevel capability [9,11,12]. Although nanometallic ReRAM can be constructed using a large variety of insulator:metal paring [7,17], here we focus on Si 3 N 4 :Pt films. We will demonstrate that Si 3 N 4 :Pt nanometallic ReRAMs can achieve ultra-fast (sub-100 ns) yet low switching voltage and 2 Journal of Nanoscience thus are promising to be implemented in future memory systems.…”