Acta Chimica Sinica ›› 2022, Vol. 80 ›› Issue (7): 936-945.DOI: 10.6023/A22030096 Previous Articles     Next Articles



孙嘉贤a,b, 刘禹廷b, 尹志刚b,c,*(), 郑庆东b   

  1. a 福州大学化学学院 福州 350108
    b 中国科学院福建物质结构研究所 结构化学国家重点实验室 福州 350002
    c 中国福建光电信息科学与技术创新实验室 福州 350108
  • 投稿日期:2022-03-02 发布日期:2022-05-05
  • 通讯作者: 尹志刚
  • 基金资助:
    国家自然科学基金(52173241); 福建省杰出青年科学基金(2019J06023); 中国福建光电信息科学与技术创新实验室(闽都创新实验室)主任基金(2021ZR116)

High-Performance Flexible Photonic Synapse Transistors Based on a Bulk Composite Film of Organic Semiconductors with Complementary Absorption

Jiaxian Suna,b, Yuting Liub, Zhigang Yinb,c(), Qingdong Zhengb   

  1. a College of Chemistry, Fuzhou University, Fuzhou 350108
    b State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002
    c Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou 350108
  • Received:2022-03-02 Published:2022-05-05
  • Contact: Zhigang Yin
  • Supported by:
    National Natural Science Foundation of China(52173241); Natural Science Foundation of Fujian Province for Distinguished Young Scholars(2019J06023); Director’s Fund of Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China(2021ZR116)

Photonic synapse transistors have attracted growing attention due to their salient advantages in information transmission/processing and good potentials for analog neural computing. Currently, most synapse transistors are rigid devices with the limitations in flexible and highly photosensitive semiconductor channel layers. To achieve high-performance flexible photonic synapse transistors, it is essential to develop stimuli-responsive organic semiconductor thin-films to broaden the photo-response range of devices and accelerate separation of photoinduced carriers for improving synaptic performances. Here, poly(3-hexylthiophene) (P3HT) and poly(indacenodithiophene-co-benzothiadiazole) (PIDT-BT) materials with complementary optical absorption have been used to fabricate a bulk composite film of organic semiconductor heterostructures by a solution-processing method. The surface structures and optoelectronic properties of the PIDT-BT:P3HT film and their single component films are studied. By using the PIDT-BT:P3HT heterostructure film as a novel photoactive channel layer, flexible low-voltage photonic synapse transistors have been designed and fabricated with the combination of polyelectrolyte-based dielectrics. The effects of different optical stimulation conditions on the performance of synapse transistors are investigated with insightful discussion on the semiconductor mechanisms. The flexible synapse transistors based on the PIDT-BT:P3HT film exhibit higher excitatory postsynaptic currents than devices with the single component semiconductor layers at the same optical stimulation. The synaptic response of the PIDT-BT:P3HT-based device is also evaluated under different stimulus variables including the optical spike wavelength, duration and frequency. As results, good synaptic characteristics are observed including the high excitatory postsynaptic current, paired-pulse facilitation, and frequency-dependent properties with the tunable synaptic plasticity. It is found that the response in excitatory postsynaptic current of the synaptic device stimulated by two beams (520 nm green laser and 685 nm red laser) together is greater than the sum of the responses stimulated by each beam alone. These results are useful for the design of high-performance photoresponsive semiconductor films and photonic synapse transistors, which are conducive to the development of low-power flexible optoelectronic devices, artificial synapses and beyond.

Key words: organic semiconductor, thin-film transistor, photonic synapse device, flexible electronics, low-voltage