In-memory light sensor provides artificial visual perception

Exploiting charge-coupled device (CCD) image sensors found in early digital cameras, Dayanand Kumar, Nazek El-Atab and colleagues have adapted and enhanced the CCD’s core structure to create memory devices that can be programmed by light. In particular, the research team embedded the two-dimensional material MoS₂ (molybdenum disulphide) into a semiconductor capacitor (MOSCAP) structure that underpins the charge-storing pixels of a CCD sensor.

The resulting Al/Al₂O₃/MoS₂/Al₂O₃/Si MOSCAP structures are claimed to function as a charge-trapping ‘in-memory’ sensor that is sensitive to visible light and can be programmed optically and erased electrically.

“The in-memory light sensors are smart multifunctional memory devices that can perform the roles of multiple - traditionally discrete - devices at once, including optical sensing, storage and computation,” El-Atab said in a statement. “Our long-term goal is to be able to demonstrate in-memory sensors that can detect different stimuli and compute.”