Synaptic transistors with a memory time tunability over seven orders of magnitude

The human brain is capable of short- and long-term memory with retention times ranging from a few seconds to several years. Electrolyte-gated transistors have drawn attention for their potential to mimic synaptic behaviors in neuromorphic applications, but they generally operate at low voltages to avoid instability and, hence, offer limited tunability. Sputtered silicon dioxide electrolytes are utilized in this work to gate indium-gallium-zinc-oxide thin-film transistors, which offer robust operation at much higher voltages. The synaptic memory behavior is studied under single and multiple pulses and under mild (1 V) and strong stimuli (up to 8 V). The devices are found to be capable of providing an extremely wide range of memory retention time from ~ 2 ms to ~ 20 000 s, over seven orders of magnitude. Furthermore, based on the experimental data on individual transistors, pattern learning and memorizing functionalities are conceptually demonstrated. Published under an exclusive license by AIP Publishing.

Automated summary

This study investigates the performance of indium-gallium-zinc-oxide thin-film transistors gated by sputtered silicon dioxide electrolytes in synaptic memory behavior. The results show that these devices are capable of providing an extremely wide range of memory retention time, while demonstrating pattern learning and memorizing functionalities.