In this study, efforts were devoted to unveiling the dual role of single crystalline Cu (5%) doped ZnO (Cu:ZnO) synthesized by a simple and low-cost chemical process and to investigate its efficacy on resistive switching (RS) applications. It was found that when Cu:ZnO was annealed at a lower temperature of 450 °C and integrated onto ITO/glass for RS applications, only oxygen mediated vacancies were responsible for its resistive switching. However, ferroelectric properties have been observed when the same Cu:ZnO was annealed at a higher temperature of 800 °C and integrated onto Nb doped SrTiO 3 . X-ray diffraction, high resolution transmission electron microscope, x-ray photoelectron spectroscopy, UV-VIS-near infrared spectrometer, and piezoelectric force microscopy (PFM) were employed to study the crystallinity, interfaces, chemical compositions, bandgap, and domains in Cu:ZnO thin films, respectively. The bandgap of Cu:ZnO was found to be 3.20 eV. PFM study exhibits the domain inversion with 180°polarization inversion by applying an external bias, evidencing its effectiveness for memory applications. When the electrical characteristics were concerned, the RS device based on this ferroelectric Cu:ZnO offers better performance, such as lower SET/RESET voltages (∼1.40 V), higher retention (up to 10 6 s) without distortion, and higher ON/OFF ratio (2.20 × 10 3 ), as compared to the former lower temperature annealed Cu:ZnO devices. A band-diagram was proposed, and transport studies were developed to understand the operational mechanism of these devices. This study explains both the limits and scopes of Cu:ZnO RS devices and formulates an idea which may accelerate the design of future generation devices.

In this paper, the impact of thermally induced self-doping and phase transformation in TiO2 based resistive random-access memory (ReRAM) is discussed. Instead of a thin film, a vertically aligned one-dimensional TiO2 nanotube array (TNTA) was used as a switching element. Anodic oxidation method was employed to synthesize TNTA, which was thermally treated in the air at 350 °C followed by further annealing from 350 °C to 650 °C in argon. Au/TiO2 nanotube/Ti resistive switching devices were fabricated with porous gold (Au) top electrode. The x-ray diffraction results along with Raman spectra evidently demonstrate a change in phase of crystallinity from anatase to rutile, whereas photoluminescence spectra revealed the self-doping level in terms of oxygen vacancies (OV) and Ti interstitials (Tii) as the temperature of thermal treatment gets increased. The electrical characterizations establish the bipolar and electroforming free resistive switching in all the samples. Among those, the ReRAM sample S3 thermally treated at 550 °C displayed the most effective resistive switching properties with R OFF/R ON of 102 at a read voltage of −0.6 V and a SET voltage of −2.0 V. Moreover, the S3 sample showed excellent retention performance for over 106 s, where stable R OFF/R ON ≈ 107 was maintained throughout the experiment.

superior to conventional computers as it is highly energy efficient, fault tolerant and has parallel processing capabilities, all this in such a small volume [2,3]. Advancements in both neuroscience and electronics have led to the area of neuromorphic computing, in which attempts are being made to incorporate certain aspects of neurobiological anatomy into the design and implementation of computing systems by implementing hardware neurons and synapses [4]. In a biological system,

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