Investigation of Electrical Properties of the Al/SiO2/n++-Si Resistive Switching Structures by Means of Static, Admittance, and Impedance Spectroscopy Measurements

Abstract

In this study, the resistive switching phenomenon in Al/SiO2/n++-Si structures is observed and studied by means of DC, small-signal admittance, and complex impedance spectroscopy measurements. Possible transport mechanisms in the high and low resistance states are identified. Based on the results of the applied measurement techniques, an electrical equivalent circuit of the structure is proposed. We discuss the effect of parasitic elements influencing the measurement results and show that a proper model can give useful information about the electrical properties of the device. A good agreement between the characteristics of the proposed equivalent circuit and the experimental data, based on different measurement procedures, confirms the validity of the used methodology and its applicability to the electrical characterization of RRAMs.

Medium-Temperature-Oxidized GeOx Resistive-Switching Random-Access Memory and Its Applicability in Processing-in-Memory Computing

“…However, in order for preserving the switching layer quality relatively more vulnerable in the LRS state and device reliability over the long-time frequency sweep period under a DC bias stress, the value was lowered to 0.7 V for the measurement in the LRS. Once the bias voltage is lower than the set voltage (~ 3.8 V in this work), it was experimentally confirmed that there was no significant change in impedance analysis results with a change in bias voltage in performing the frequency sweep [ 44 ]. As the frequency goes higher, the trajectory is plotted in the counterclockwise direction.…”

Resistive switching study on diffusive memristors using electrochemical impedance spectroscopy

“…Between the HRS and LRS, memristors can, in general, possess resistive, capacitive and inductive properties to some degree [18]. Specifically, this resistive and capacitive behavior is observed in the HRS while some inductive characteristics are displayed in the LRS [19,20]. Therefore, when studying such devices, it is opportune to apply a characterization technique capable of isolating and measuring all three of these properties.…”

“…EIS has been used in the past to study mostly non-volatile memristors, for example, ones with switching layers of TiO x [18,19,[25][26][27][28][29], SiO x [19,28,30], Cu/SiO 2 [28], HfO 2 [27], WO x [22], Ge 2 Sb 2 Te 5 [31] and Ag/Si [32]; both in the HRS and LRS. The only comparable example of an EIS study on a volatile memristor that we are aware of was [20].…”

“…For example, EIS allows one to identify relatively easily whether the switching layer consists of a single or several sub-layers [25], contains the additional electrode interface active in a switching layer [34] or several material layers, as in Dash et al [29], where double arcs were identified in Nyquist plots and linked to TiO x and TiO 2 layers. Furthermore, it can be easily seen whether the impedance is dominated by the capacitive or inductive elements; the latter assumed to be linked to conductive, mostly metallic filaments [19,20,27] whilst a leaky insulating layer, typically in HRS, is modeled as a capacitor with a parallel resistance [20,23,25,30]. Sometimes, one also observes a phenomenon at lower frequencies often referred to as the 'inductive hook' related to diffusion of ions [25,26,34,35] and visible as an inductive arc contribution at lower frequencies.…”

Investigation of the Temperature Effect on Electrical Characteristics of Al/SiO2/n++-Si RRAM Devices

“…Some works have presented research on SiO 2 as a promising material for those devices [ 17 , 18 , 19 , 20 ]. In our recent works, we showed that well-known silicon oxide in a materials stack of Al/SiO 2 /n++-Si can also exhibit resistive switching properties [ 21 , 22 ]. However, little work relates to the effect of temperature on the device’s performance [ 23 , 24 , 25 ].…”