Anodic HfO2 crossbar arrays for hydroxide-based memristive sensing in liquids

Abstract

The development of miniaturized and portable sensing devices is crucial to meeting the high processing capacity demands of contemporary computing systems. Hence, the conceptualization of memristive sensors for hydroxide-containing liquids is proposed in this study. Metal-insulator-metal (MIM) structures were formed on electrochemically anodized Hf thin films with Pt patterned as top electrodes. These MIM memristive structures were integrated into a crossbar array, allowing the investigation of a high number of potential memristor sensors. The MIM structures have demonstrated sensing possibilities in the detection of the hydroxyl ion in D-glucose, used as a standard solution. The sensing method was based on the resistive state ratio extracted from I-U sweeps measurements. Analytical characterization of the memristor sensor was done based on the resistive state ratio in relation to different concentrations of a standard solution drop cast directly on the surface of the device. Linearity was found for D-glucose concentrations ranging from 10 mM to 80 mM with a reasonable corresponding correlation factor (R2=0.96809). Additionally, D-glucose incorporation in anodic oxide was studied by XPS to investigate its effect on conductive filaments formation. A carbon bonded by a single covalent bond to oxygen (O-C-O) was detected, confirming the proposed sensing mechanism defined by the glucose penetrating the oxide/electrode interface.

Electrolyte Influence on Properties of Ultra-Thin Anodic Memristors on Titanium

“…Digital memristors typically have a filamentary switching mechanism, while analog devices have a non-filamentary one based on an interfacial switching mechanism [11,13]. Depending on their unique resistive switching properties, such as volatile or non-volatile and digital or analog behavior, memristors are utilized for various use-cases such as image processing [14,15], sensing of OH − species [16][17][18], memory [19][20][21][22] or neuromorphic computing [23][24][25][26][27][28].…”

Interfacial Resistive Switching of Niobium–Titanium Anodic Memristors with Self-Rectifying Capabilities

“…The switching mechanism of digital memristors is usually filamentary, while analogue ones may have either filamentary, with parallel filaments defining the resistive levels [ 4 , 5 ], or nonfilamentary mechanisms, based on an interfacial switching mechanism [ 6 ]. With its unique volatile or non-volatile resistive switching behaviour, this circuit element (the fourth most common apart from the inductor, capacitor, and resistor) can be used in a variety of modern applications such as memory devices [ 7 , 8 , 9 , 10 , 11 , 12 , 13 ], sensing [ 14 , 15 , 16 ], image processing [ 17 , 18 ], and neuromorphic computing [ 19 , 20 , 21 ].…”