Brain-like synaptic operations of thin-film transistors using In-Ga-Zn-O active channel and PVP-SBA electrolytic gate insulator

We proposed a synapse thin film transistors with a bottom-gate structure composed of an In-Ga-Zn-O (IGZO) active channel and a poly 4(vinylphenol)-sodium beta-alumina (PVP-SBA) gate insulator. The physical and electrical properties of the PVP-SBA were demonstrated as an electrolytic gate insulator for the synapse TFTs. Paired-pulse facilitation (PPF), short-term memory (STM), and long-term memory (LTM) operations were successfully confirmed in the fabricated synapse TFTs, in which output drain currents were effectively modulated with various input pulse conditions owing to the electrostatic coupling between the carriers in IGZO channel and sodium ions in PVP-SBA in the STM operation and electrochemical doping in the LTM operation, respectively.