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In this paper, we demonstrate the linear conductance-change characteristics of a conductive-bridging RAM (CBRAM) to be employed as an artificial synapse device in neuromorphic systems. The CBRAM with a bilayer electrolyte structure (${\mathrm {Cu/Cu}}_{{2}-{x}}\text{S}$ / $\mathrm {WO}_{{3}-{x}}$ /W) exhibits analog switching behavior during the depression process due to the well-controlled dissolution of the conductive filament. To analyze the origin of this motion, we investigate the effective voltage applied to $\mathrm {Cu}_{{2}-{x}}\text{S}$ and $\mathrm {WO}_{{3}-{x}}$. Our findings reveal that $\mathrm {Cu}_{{2}-{x}}\text{S}$ , acting as a voltage divider, helps in suppressing the large voltage drop in $\mathrm {WO}_{{3}-{x}}$ , where the formation/dissolution of filament occurs. Furthermore, due to the diode-like characteristics of $\mathrm {Cu}_{{2}-{x}}\text{S}$ and the division of voltage drop between $\mathrm {WO}_{{3}-{x}}$ and $\mathrm {Cu}_{{2}-{x}}\text{S}$ , an optimum programming energy is applied to $\mathrm {WO}_{{3}-{x}}$ during the depression process. This leads to linear conductance-change characteristics under identical pulses. However, abrupt conductance-change characteristics are observed during the potentiation process. Thus, we use only the device characteristics of the depression part for the neuromorphic system. An excellent classification accuracy is achieved due to the linear conductance-change characteristics and optimized pulse conditions. [ABSTRACT FROM AUTHOR]

Conductive bridge random access memory (CBRAM) is a possible replacement for static field‐programmable gate arrays (FPGAs) based on random‐access memory. Ge2Sb2Te5 (GST) is used in CBRAMs as a solid electrolyte due to its high diffusion properties of active ions and scalability to obtain high‐density memory devices. Here, the trade‐off between high memory window and uniformity of CBRAM based on GST is solved by introducing N atoms into the SE. Nitrogen‐incorporated GST film (N‐GST) is proposed as a replacement for the current GST‐based CBRAMs with improved performance and better opportunities for conventional FPGA technologies. A bidirectional polarity‐dependent characteristic with high ION/IOFF ratio and satisfactory operation voltage is achieved by using N‐GST thin film in a programmable metallization cell (PMC). Integration of N atoms in the GST‐based PMC with a simple structure of Ag/ N‐GST /Pt increases the resistance ratio more than 100 times compared to an undoped one. Consistent data retention is attained in both resistance states for ≥3.5 × 104 s at temperature up to 85 °C. A nanoscale conductive bridge random access memory (CBRAM) based on phase change material is demonstrated. Nitrogen‐incorporated Ge2Sb2Te5 (N‐GST) film is proposed as a replacement for the current GST‐CBRAMs with improved performance and better opportunities for conventional field‐programmable gate arrays technologies. A bidirectional polarity‐dependent characteristic with high ION/IOFF ratio and satisfactory operation voltage is achieved in a programmable metallization cell. [ABSTRACT FROM AUTHOR]