【Epitaxy Papers】Enhancing the photoelectric synaptic plasticity of β-Ga₂O₃ films via improving crystalline quality

      Researchers from the Dalian University of Technology have published a dissertation titled "Enhancing the photoelectric synaptic plasticity of β-Ga₂O₃ films via improving crystalline quality" in Journal of Alloys and Compounds.

Abstract

      Solar-blind ultraviolet (SBUV) photoelectric bionic synapses, which has the advantages of anti-interference, high-speed transmission, computing-in-memory, is considered to help solve the severe challenges faced by the Von Neumann architecture computers. Diverging from conventional photodetectors (PDs), photoelectric bionic synapses necessitate robust synaptic plasticity—a trait that entails sustaining an excited state for extended periods post-optical stimulation. Traditionally, the photoelectric synaptic plasticity observed in gallium oxide (Ga₂O₃) has been attributed to the presence of defects, with high crystalline quality often deemed detrimental to such functionalities. However, in this paper, by enhancing the crystalline quality of β-Ga₂O₃ films, we significantly boost the synaptic plasticity of the device, extending the recovery time of the devices from 0.22 s to over 40 s. Furthermore, the synaptic device boasts multifaceted functionalities, including multi-level storage, short-term memory (STM), and long-term memory (LTM). Besides, the device demonstrates excellent voltage stability (under 1-10 V) and high-temperature operability (at 630 K). Combined with the analysis of film characteristics, we posit that the synaptic plasticity exhibited by these high-quality β-Ga₂O₃ films stems from its intrinsic indirect bandgap.

DOI：

https://doi.org/10.1016/j.jallcom.2025.179771