Photoelectrical reading in ZnO/Si NCs/p-Si resistive switching devices

Abstract

The increasing need for efficient memories with integrated functionalities in a single device has led the electronics community to investigate and develop different materials for resistive switching (RS) applications. Among these materials, the well-known Si nanocrystals (NCs) have demonstrated to exhibit RS properties, which add to the wealth of phenomena that have been studied on this model material platform. In this work, we present ZnO/Si NCs/p-Si resistive switching devices whose resistance state can be electrically read at 0 V under the application of low-power monochromatic illumination. The presented effect is studied in terms of the inner structural processes and electronic physics of the device. In particular, the creation of conductive filaments through the Si NC multilayers induces a low-resistance path for photogenerated carriers to get extracted from the device, whereas in the pristine state charge extraction is strongly quenched due to the insulating nature of the NC-embedding SiO2 matrix. In addition, spectral inspection of the generated photocurrent allowed unveiling the role of Si NCs in the reported effect. Overall, the hereby shown results pave the way to obtain memories whose RS state can be read under low-power conditions.