论文信息 - Improvement of Memory Retention Characteristics in Ferroelectric Neuron Circuits Using a Pt/SrBi2Ta2O9/Pt/Ti/SiO2/Si Structure-Field Effect Transistor as a Synapse Device.

Improvement of Memory Retention Characteristics in Ferroelectric Neuron Circuits Using a Pt/SrBi2Ta2O9/Pt/Ti/SiO2/Si Structure-Field Effect Transistor as a Synapse Device.

A metal-ferroelectric-metal-oxide-semiconductor field effect transistor (MFMOS-FET) with a Pt/SrBi2Ta2O9/Pt/Ti/SiO2/Si structure was fabricated on a silicon-on-insulator (SOI) structure in order to improve the memory retention characteristics of ferroelectric neuron circuit. The area ratio of MOS capacitor to MFM capacitor was changed from 3 to 15 so that charge quantities induced in both capacitors were optimized. It was found that the memory operations and retention characteristics were considerably improved in the fabricated MFMOS-FET with an area ratio larger than 10, compared with those of the MFSFET previously fabricated using a Pt/SrBi2Ta2O9/Si structure. Next, a pulse frequency modulation (PFM)-type neuron circuit was fabricated using the MFMOS-FET and a CMOS Schmitt-trigger oscillator as a synapse and a neuron, respectively, and it was found that the oscillation frequency of the circuit remained almost unchanged over a period of 1 h.

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