Ferroelectric-based synaptic device and method of operating the synaptic device, and 3D synaptic device stack using the synaptic devices

A method of operating a ferroelectric-based synaptic device which comprises a source, a drain, a semiconductor body having a channel region, a gate electrode, and an insulating layer stack disposed between the semiconductor body and the gate electrode, wherein the insulating layer stack includes a charge trap layer made of a material capable of storing or trapping electric charges and disposed on the channel region, a ferroelectric layer made of a ferroelectric material, and an insulating layer disposed between the charge trap layer and the ferroelectric layer,

• the method of operating a ferroelectric-based synaptic device comprises the following steps:
• (a) storing charges corresponding to weight information of the ferroelectric-based synaptic device in the charge trap layer;
• (b) applying a pulse voltage to the gate electrode;
• (c) polarizing the ferroelectric layer according to the amount of charge stored in the charge trap layer by the pulse voltage applied to the gate electrode;
• and
• (d) leaking the charges stored in the charge trap layer to the channel region, and
• wherein charges corresponding to the weight information of the ferroelectric-based synaptic device are temporarily stored in the charge trap layer, and the weight information of the ferroelectric-based synaptic device is non-volatilely stored in the ferroelectric layer.