Remarkable improved photoelectric performance of SnS2 field-effect transistor with Au plasmonic nanostructures

The photoelectric devices developing towards the high integration and miniaturization in semiconductor industry can be pushed forward by the thriving research of two-dimensional layered metal dichalcogenides (2D-LMDs). SnS2 nanosheets have evident photoresponse to both ultraviolet and partial visible light, but only with a fair photoelectric performance limited by its atomic-layer thickness. Here we report a convenient and simple method to make a dramatic enhancement of the electrical and photoelectric performance of the SnS2 flake. By integrating SnS2 with Au plasmonic nanostructures, the photocurrent (Iph) increased by over 20 times. And the corresponding responsivity (R), light gain (G), and detectivity (D*) have been improved by ~2200%, 2200%, and 600%, respectively. The responsivity and detectivity of the Au NPs-SnS2 FET at 532 nm are 1125.9 A/W and 2.12×1011 Jones. Though being atomically thin, the hybrid SnS2 photodetector benefiting from local surface plasmonic resonance achieves an excellent photoelectric performance not normally possible with the pristine SnS2-only device.