Analysis and simulation of the multiple resistive switching modes occurring in HfOx-based resistive random access memories using memdiodes

Abstract

In this work, analysis and simulation of all experimentally observed switching modes in hafnium oxide based resistive random access memories are carried out using a simplified electrical conduction model. To achieve switching mode variation, two metal-insulator-metal cells with identical stack combination, but varying oxygen stoichiometry of the hafnia layer, namely, stoichiometric vs highly deficient, are considered. To access the individual switching modes, the devices were subjected to a variety of cycling conditions comprising different voltage and current ranges. For modeling the device behavior, a single or two antiserially connected memdiodes (diode with memory) were utilized. In this way, successful compact simulation of unipolar, bipolar, threshold, and complementary resistive switching modes is accomplished confirming the coexistence of two switching mechanisms of opposite polarity as the basis for all observable switching phenomena in this material. We show that only calibration of the outer current–voltage loops with the memdiode model is necessary for predicting the device behavior in the defined region revealing additional information on the switching process. The correspondence of each memdiode device with the conduction characteristics of the individual top and bottom metal-oxide contacts allows one to assess the role played by each interface in the switching process separately. This identification paves the path for a future improvement of the device performance and functionality by means of appropriate interface engineering.

Application of the Quasi-Static Memdiode Model in Cross-Point Arrays for Large Dataset Pattern Recognition

“…This model is called the quasi-static memdiode model (QMM) and is the central subject of our analysis. Remarkably, the QMM has been explored so far as a single device or as simple series/anti-series/parallel/antiparallel connections (just two devices) [39]- [41], and its application to the case of large CPAs for pattern recognition tasks is still to be addressed. This is the central topic of this work.…”

2D Resistive Switching Based on Amorphous Zinc–Tin Oxide Schottky Diodes

“…[11,12] This can be referred to as 3D RS. [14][15][16][17] In addition, the choice between digital and analog operation modes by different device initialization schemes has been reported for NiO-based devices. [13] Another type of area-dependent RS exists when ions are exchanged (or trapping occurs at the interface) between the switching matrix and the electrode.…”

“…[14][15][16][17] In addition, the choice between digital and analog operation modes by different device initialization schemes has been reported for NiO-based devices. The direction of the switching loops is opposite to 1D RS and 3D RS, that is, eightwise (8w) when the bias is applied to the current blocking electrode.…”

Tailoring the Switching Dynamics in Yttrium Oxide‐Based RRAM Devices by Oxygen Engineering: From Digital to Multi‐Level Quantization toward Analog Switching

“…The exact mechanisms, role of interfaces and nature of the conducting filament is still under debate. [14][15][16][17] When the size of the conducting filament reduces to the atomic scale, eventually conductance quantization phenomena may be observed even at room temperature. The quantum conductance unit is defined as G 0 = 2e 2 /h, [18] where e is the electron charge and h the Planck constant, and equals 77 µS or (12.9 kΩ) −1 .…”