3D Stackable Broadband Photoresponsive InGaAs Biristor Neuron for a Neuromorphic Visual System with Near 1 V Operation

A photoresponsive InGaAs biristor neuron suitable for neuromorphic visual systems is demonstrated. It receives optical signals, converts them to electrical signals, and simultaneously transmits spiking signals to a neural network. This feature is attractive for an input neuron in spiking neural networks (SNNs). A visible and infrared (IR) light photoresponse with near 1 V operation was achieved thanks to the narrow bandgap energy of the InGaAs. This permits broadband detection with lower energy consumption and higher speed compared to previous Si-based neurons. Furthermore, monolithic 3D integration (M3D) of photoresponsive neurons over the synapses is available to construct a 3D neuromorphic visual system, which also minimizes the interconnect bottleneck because of its inherently low temperature fabrication.