Controlled Optoelectronic Response in van der Waals Heterostructures for In‐Sensor Computing

Abstract

In-sensor computing with visual information, which can integrate photosensing, data storage, and computation functions within the same physical element, has promised a fundamentally different architecture for future machine vision technology with extreme energy and time efficiency. The elementary devices required to fulfil the goal of such a new sensory computation scheme would demand a bold functional variation to the existing sensor and data processing hardware. Here, a van der Waals (vdW) heterostructure-based optoelectronic transistor that can act as an integrated photoreceptor, memory, and computation unit by exploiting its own physical attributes is demonstrated. It is found that diverse photoelectric control of device conductance can lead to versatile photoresponse characteristics, including memristive behaviors, retention-, polarity-and strength-tunable photoconductance, photoelectric-coupling effect, etc. Exploiting the photoelectric-coupling effect, reconfigurable and nonvolatile optoelectronic logic functions are realized in this device, featuring a logic-insensor unit. With the same device, both short-and long-term synaptic plasticity can be faithfully emulated, rendering it an optoelectronic synaptic transistor. Moreover, a psychologic human memory model is implemented with the device, showing the emulation of memorization and learning processes. This prototypical demonstration provides a promising hardware system for visual information in-sensor computing capable of addressing complex computation tasks.

Fully-Depleted Silicon-on-Insulator (FDSOI) Based Complementary Phototransistors for In-Sensor Vector-Matrix Multiplication

“…2(b) shows the measured CPT I D with exposure operation. Similar to the 2D-metarial phototransistors in the existing reports [11], [12], [13], [18], the Gate-Source voltage (V G S ) and Drain-Source voltage (V DS ) are kept constant for photo-sensing. However, these existing reports are only applied with DC signals for photo-sensing while the voltage applied on Base (V B ) of CPT should be a negative voltage pulse.…”

“…The vector-matrix multiplication (VMM) is the basis of the artificial neural network (ANN) for image processing. To realize the in-sensor VMM, the foundation is the sensor unit with bidirectional and tunable photoresponsivity (BTP) [11], [12], [13], [14], [15]. Both positive and negative photoresponsivity are essential to the sensor unit and the sensitivity are required to be tunable by electrical signals.…”

“…Both positive and negative photoresponsivity are essential to the sensor unit and the sensitivity are required to be tunable by electrical signals. For example, the phototransistors based on the 2D materials for the insensor VMM have been demonstrated, which rely on the BTP caused by the gating effects in 2D materials [11], [12], [13]. Meanwhile, benefit from the ion migration in perovskite [14] or the ferroelectric polarization modulation [15], the perovskite and ferroelectric heterostructure have also been employed to realize the in-sensor VMM.…”

Low-Dimensional-Materials-Based Flexible Artificial Synapse: Materials, Devices, and Systems

“…Therefore, energy efficient in-sensor computing devices, fabricated with low-dimensional materials, show great potential applications in neuromorphic engineering [ 32 , 33 , 34 ]. In this review, the electrical and mechanical properties of low-dimensional materials, as well as corresponding advantages in the fabrication of flexible electronic devices, will be introduced.…”

Probing switching mechanism of memristor for neuromorphic computing

“…Neuromorphic computing systems perform data storage and processing by mimicking the human brain's biological structure, including synapses and neurons, using electronic devices [17][18][19][20][21][22][23][24]. The concept of memristors has been proposed by Leon O. Chua in 1971 [25], in which they represent the relationship between magnetic flux and electric charge.…”