Li Memristor-Based Mosfet Synapse For Linear I-V Characteristic And Processing Analog Input Neuromorphic System

In this research, we propose a method that can significantly improve the linearity of current-voltage characteristics (L-IV) of synapse devices. Considering that analog input data are dependent on the L-IV, synapse devices having non-linear current-voltage characteristics can result in drastic conductance variations during inference operations. It means that the L-IV is one of the key parameters in the synapse device. To improve the L-IV, a triode region of a metal oxide semiconductor field effect transistor (MOSFET) was utilized with a Li-ion-based memristor as a gate voltage divider, which results in gradual channel conductance changes (analog synaptic weights). The channel conductance of the MOSFET can be selectively controlled based on Li-ion intercalation and de-intercalation. A notably improved L-IV and analog synaptic weights were achieved, which enhanced the MNIST data set recognition accuracy from 35.8% to 92.03%.