(Invited) Brain-like Synapse Thin-Film Transistors Using Oxide Semiconductor Channel and Solid Electrolytic Gate Insulator

We proposed a synapse thin film transistors with a top-gate structure composed of an In-Ga-Zn-O (IGZO) active channel and a Li-incorporated polypropylene carbonate (Li:PPC) gate insulator. The physical and electrical properties of the PPC were investigated for the use as an electrolytic gate insulator of the synapse TFTs. Synaptic behaviors including the paired-pulse facilitation (PPF) 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 lithium ions in PPC.