Highly sensitive MoS2 photodetector on polarized thin-film lithium niobate with extremely low dark current

To obtain high performance optoelectronic devices, ferroelectric materials have received a lot of attention due to the various emerging effects on channel materials induced by the ferroelectric polarization. In this work, a special photodetector with the channel material of a triple-layer MoS2 on a polarized LiNbO3 substrate was fabricated. The device has a high responsivity of 113.1A/W and a high specific detectivity of up to 7.286x10(12) Jones under red illumination, while maintaining the rise and fall time of 32 and 22ms, respectively. Meanwhile, the dark current of this device can be as low as 2.66x10(-11)A with a bias of 5.0V because the channel material MoS2 is almost depleted under the internal electrical field induced by the polarized LiNbO3. This work promises a feasible way for the future development of integrated high-sensitivity photodetectors.