【Device Papers】Circuit Emulating Neural Response Based on Ga₂O₃ Photomemristor

      Researchers from the Universidade Federal do ABC have published a dissertation titled "Circuit Emulating Neural Response Based on Ga₂O₃ Photomemristor" in physica status solidi (b).

Abstract

      Gallium oxide (Ga₂O₃), a transparent semiconductor material with  wide bandgap between 4.5 and 4.9 eV, has attracted increasing interest lately due to multifunctionality. In this work, Ga₂O₃ films are deposited by ion-beam-assisted deposition method on p-type silicon at ≈800 °C. Films deposited at lower temperatures predominantly have β-phase structure, while those deposited at higher temperatures have dominant ε-phase structure. Memristors testing devices are fabricated by depositing aluminum contacts over the Ga₂O₃ surface and the back surface of the substrate. In the Rutherford backscattering structural analysis, it is indicated that there is aluminum diffusion from the top contact into the film. The current–voltage measurement of the isolated device provides key information for understanding the memristor operation, revealing its bipolar characteristic and responsiveness to visible-light soaking. The resistive switching behavior involving filament formation due to oxygen vacancies is discussed; however, since there is a light response, the most plausible explanation for the resistive switching is the trapping/detrapping mechanism. In the proposed neuromorphic circuit measurement, it is aimed to use a circuit that emulates a neuronal membrane and study the behavior of memristors response to light stimulus. This approach proves to be an excellent tool for observing action potentials, which mimic human vision.

DOI：

https://doi.org/10.1002/pssb.202400484