Ningbo Materials has made progress in the research of new photovoltaic / synaptic thin film transistors
Thin-Film Transistors (TFTs) are the most basic and important three-terminal electronic components in the semiconductor industry, and have been widely used in consumer products such as flat panel displays and radio frequency tags. In recent years, TFTs have gradually attracted people's attention in the fields of photoelectric detection and photosensitive synapses. Compared with traditional two-terminal devices, photoelectric TFTs have the following outstanding advantages: the use of gate voltage control degrees of freedom of TFTs can realize the integration of signal detection and amplification, which is beneficial to the simplification of later circuit design and reduce system power consumption; photodetection TFTs and Traditional electrical functions (switching, driving, address selection, etc.) TFTs have the same structure and process compatibility, are easy to integrate (even pixel integration), and help to increase the flexibility of system design. Ultraviolet photodetectors have important applications in the fields of national defense, power grid security monitoring, medical imaging, marine search and rescue, environmental and biochemical detection, forest fire alarms, etc., and are the focus of research and development in countries around the world. In recent years, the research team of Cao Hongtao of the Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences has implemented the coupling of two- and three-terminal devices by modifying the p-type PEDOT: PSS thin film on the back channel surface of the depletion SnOx / IGZO thin film transistor. High-performance visible blind ultraviolet photodetection TFTs. Due to the full use of the advantages of both ends (the built-in electric field in the vertical direction to separate charges) and the three-terminal device (lateral source-drain electric field to collect charge), the photoelectric response and photosensitivity of the device have been significantly improved. The above results were published in ACS Appl. Mater. Interfaces 2018, 10, 8102-8109. In addition, "artificial intelligence (AI)" has become one of the global research hotspots, and synapse is one of the important basic tools for building artificial neural networks based on the device level. The team built a highly sensitive and low-power optoelectronic device that simulates visual synapses on the basis of the previous work on the coupling device. The device works in the visible and ultraviolet regions, has long-range and short-range plasticity, and has selective memory and Forget function. It is responsive to blue light pulses with a signal strength as low as 1μW / cm2, and the electrical power consumption of a single device is less than 10pW, and can realize optical writing and electrical erasing functions. The idea of ​​using a high-k gate dielectric to further reduce the operating voltage, the team also built a fully transparent visible light responsive photosensitive synapse device, the device can respond to weak light, and lower energy consumption. The above results were published in Nano Energy 2019, 62,772-780. The above work was supported by the National Natural Science Foundation of China, the Key International Cooperation Project of the Chinese Academy of Sciences, the Ningbo Science and Technology Innovation Team and the Ningbo Natural Science Foundation. Figure 2 The schematic scheme of the photosensitive nerve synapse device used for visual simulation and the performance demonstration of the coupling device in terms of long-range, short-range plasticity and wide spectral response Stainless Steel Pipe Nipples,Stainless Steel Pipe Nipple ,Stainless Tube Fittings,Stainless Steel Union WENZHOU DIYE VALVE&FITTINGS CO.,LTD , https://www.diye-valve.com
Figure 1 Working principle and photoelectric response performance of pn junction and TFT coupling devices