Realization of artificial synapse and inverter based on oxide electric-double-layer transistor gated by a chitosan biopolymer electrolyte

作者：Lu, Guangpan; Liu, Yurong^*; Lin, Feng; Gen, Kuiwei; Wu, Weijing; Yao, Ruohe

来源：Semiconductor Science and Technology, 2020, 35(7): 075014.

DOI：10.1088/1361-6641/ab883e

• electric-double-layer transistor
• zinc oxide
• chitosan electrolyte
• artificial synapse
• inverter

Low-voltage transparent zinc oxide (ZnO) thin-film transistor with chitosan biopolymer electrolyte as a gate dielectric was fabricated at room temperature and characterized. Due to an electric-double-layer (EDL) effect near the chitosan/ZnO interface through mobile-proton migration, the transistor exhibits a good performance with a carrier mobility of 7.88 cm(2)V(-1)s(-1), a threshold voltage of 1.0 V, an on-off current ratio of 5 x 10(4), a subthreshold slope of 135 mV Dec(-1), and an operating voltage of less than 3 V, respectively. Based on the EDL transistor, the excitatory post-synaptic current and paired-pulse facilitation (PPF) behavior of biological synapses are mimicked, and PPF index is related to the inter-spike interval of the paired pulse. Furthermore, the resistor-loaded inverter based on the transistor was built, showing a high voltage gain of similar to 4 at a low supply voltage of 3 V, a small delay, a large noise margin and a low power consumption. The EDL transistor may ?nd potential applications in portable electronics and synaptic electronics.