Single transistor with double gate structure for adjustable firing threshold voltage, and neuromorphic system using the same

An operation method of a single transistor neuron with a double gate structure comprising a driving gate and a control gate independently separate from each other, the method comprising:

• inputting a current signal from a previous synaptic device to a source or a drain;
• storing charge by the current signal in a transistor;
• outputting a voltage signal in a form of a spike when a source voltage or a drain voltage increasing according to the stored charge reaches a firing threshold voltage or more;
• and
• adjusting the firing threshold voltage through the control gate if a frequency of the output voltage signal deviates from a preset normal range,
• wherein the single transistor neuron with the double gate structure integrates a signal when a current signal is applied to the source or the drain and outputs a voltage signal in a form of a spike from the source or the drain if the integrated signal reaches a predetermined level or more.

A single transistor neuron with a double gate structure, the single transistor neuron comprising:

• a barrier material layer formed on a semiconductor substrate and comprising a hole barrier material or an electron barrier material;
• a floating body layer formed on the barrier material layer, the floating body layer having first, second, third, and fourth sides;
• a source and a drain formed at the third and fourth sides of the floating body layer, respectively;
• a driving gate formed at the first side of the floating body layer without contacting the source and the drain;
• a control gate formed at the second side of the floating body layer without contacting the source and the drain;
• and
• a gate insulating film formed between the floating body layer and the driving gate and between the floating body layer and the control gate,
• wherein the single transistor neuron with the double gate structure implements an inhibitory function of inhibiting a spike action of a neuron by inputting an inhibitory signal to the driving gate, integrates the signal when a current signal is applied to the source or drain, and outputs a voltage signal in the form of a spike from the source or drain when the integrated signal reaches a predetermined level or higher.