ã€Research and Development of China Instrument Network Instrumentation】 Recently, the research team of Shen Guozhen, a national key laboratory of the semiconductor superlattice of the Chinese Academy of Sciences, cooperated with Prof. Chen Xiao of the School of Mathematics and Physics of the Beijing University of Science and Technology to make new progress in the field of flexible artificial visual perception and storage systems. .
The human visual system can not only be used to sense external light information, but also to store the perceived information in the brain's nervous system. In recent years, researchers have made significant progress in simulating human visual perception through the research of image sensor arrays. However, although the current image sensor realizes recognition capabilities for some simple graphics, when the external light disappears, the sensed graphics information also disappears, and the storage function of the sensing information cannot be realized. In order to compensate for this defect and achieve bionic simulation of the human visual system, a reasonable integration of the image sensor device with the memristive device will be an effective way.
In order to realize the detection and memory function of integrated electronic devices for light information, Dr. Chen Shuai, a doctoral student in the joint team, and Assistant Professor Fang Zhengzheng, jointly developed a bionic flexible visual perception and storage system. The system integrates an image sensor device based on an indium oxide semiconductor microwire array and an aluminum oxide resistive memristor device based on atomic layer deposition. Through external UV light excitation, the image sensor's resistance state will change from a high-impedance state to a low-impedance state. When the resistance value is reduced to a certain value, the voltage across the memristive device in series will reach the memristor's turn-on voltage, and then the memristor will be excited to switch from the high-impedance state to the low-resistance state. These two states correspond to logic respectively. The off(1) and on(0) states in the circuit. In this way, when the external ultraviolet light disappears, although the image sensor device will return to the initial state, its perceived light information has been stored in the memristor in binary form. In addition, the 10x10 visual memory array device assembled by expanding the pixel density of the device array can also realize the perception and storage functions for the external image-type light distribution. The artificial system exhibits a long-term information memory function that can stabilize memory for up to a week. Moreover, by applying a negative voltage across the memristor, the stored light distribution information can be erased, and the light distribution information of other images can be stored again, thereby realizing the reusability of the integrated device.
The flexible artificial vision system designed by this work has great application potential in future wearable devices, electronic eyes, multifunctional robots, and auxiliary equipment for the visually impaired, and it is designed to design new types of flexible multi-function sensing and Memory integration devices such as tactile memory systems and auditory memory systems provide new ideas.
This work has been supported by the National Outstanding Young Scientists Fund, the Beijing Municipal Natural Science Foundation, and the Frontier Science Key Research Project of the Chinese Academy of Sciences. The research results were recently published in the journal of Advanced Materials (DOI: 10.1002/adma.201705400).
(Original Title: New Progress Made in the Field of Flexible Artificial Visual Sensing and Storage Systems for Semiconductors)