ferroelectric field effect transistor 2

The basic structure and storage mechanism of ffet

The basic structure of the ffet unit is the MFS-FET structure, which replaces the gate dielectric layer in MOS FET with a ferroelectric thin film. The polarization state of the ferroelectric thin film is used to modulate the surface state of the semiconductor, thereby modulating the conduction state between the source and drain of the transistor, distinguishing between logic states "0" and "1", in order to achieve the purpose of storing information. As shown in Figure 1.

Figure 1n Schematic diagram of the basic structure of channel ffet

When an external positive voltage greater than the coercive field is applied to the gate, the ferroelectric thin film undergoes positive polarization, transistor and the electric field points towards the semiconductor surface, attracting negative compensation charges to the semiconductor surface. For n-type silicon substrates, the surface is in an accumulation state, and the FET device is in an off state. When an external negative voltage greater than the coercive field is applied to the gate, the ferroelectric thin film generates negative polarization, attracting positive compensation charges to the semiconductor surface. The n-type silicon surface is depleted until inversion, at which point the channel is conductive. If a bias voltage is applied to the source and drain, a current ids can be generated. Therefore, transistor corresponding to the positive and negative polarization states of ferroelectric thin films, the silicon surface exhibits two states: accumulation and inversion. When a voltage is applied to the source and drain,transistor  the FET is in two states: off and on. The two polarization states of the ferroelectric thin film are equally stable, and the corresponding semiconductor surface is stable. At this point, the on and off states of the FET can achieve the storage of binary "0" and "1",