Wafer-Scale, Efficient In₂S₃-Based Optical Memory Devices for Neuromorphic Computing

This article demonstrates fabrication and testing of novel memory devices using indium sulfide(In2S3) as an active material. A wafer scalable process is used to develop nanostructured In2S3 for the mass pro-duction of optical memory devices. The developed device shave shown outstanding light-sensing capability as well as memory functionality. The In2S3 devices are highly responsive toward the 880 nm with higher responsivity and detectivity of 15.88 A/W and 2.84x10(11)Jones, respectively. In addition, these optical memory devices were able to mimic cognitive functionalities like high paired-pulse facilitation (PPF) index, long-term plasticity (LTP),and short-term plasticity (STP) compared to the state of the art. The optical memory devices have shown a higher PPF index of 227% and long-term memory (LTM) retention capability of 2x10(3)s. Devices were optically potentiated for broadband spectrum and reset using electrical stimulation. Moreover, In2S3-based devices have highly repeatable, scalable, stable, and reproducible characteristics at room temperature with a rise/fall time of 0.4/0.01 s. The fabricated optical memory devices can be deployed for future neuro-morphic computing applications.