Fabrication of field effect transistor based on deuterated glycinium phosphite crystal and pentacene

We have fabricated a field effect transistor (FET) based on an organic ferroelectric insulator, a deuterated glycinium phoshite (D-GPI) and a pentacene film and have investigated electrical properties on the prepared FETs. It is observed that the FET based on D-GPI and pentacene film becomes a normally-on p-type FET. Moreover, we have observed that the gate electric field EG dependence of drain current iDS in the prepared FET displays the characteristics of hysteresis. This result indicates that the FET based on the D-GPI and pentacene film shows a memory effect Furthermore, we have found that the area of the iDS-EG hysteresis curve in the FET based on the D-GPI and pentacene film is determined by the magnitudes of the spontaneous polarization and coercive electric field of the D-GPI. On the basis of these results, it is also ascertained that the spontaneous polarization in the D-GPI insulator is responsible for the surface charge at the interface between the D-GPI and pentacene film. Furthermore, these results indicate that the values of iDS and the formation of the depletion layer largely depend on the spontaneous polarization and coercive field of the D-GPI insulator. Moreover, it is deduced that we can control the appearance of the depletion layer by controlling the deuterated ratio, which is responsible for the spontaneous polarization and coercive field of GPI insulator.