Nonvolatile and tunable switching of lateral photo-voltage triggered by laser and electric pulse in metal dusted metal-oxide-semiconductor structures

High voltage endurance and switchable resistance effect observed in nanoscale copper groove structure

A switchable lateral resistance effect with high reverse voltage has been observed in nanoscale copper groove structure. With the stimulation of electric pulse and local illumination of laser, the lateral resistance of the structure can be modulated in a non-volatile manner. We attribute this phenomenon to the different width of depletion region and the Schottky barrier change caused by the nanoscale charge trapping effect. This work may inspire a new approach of resistance modulation and help the development of laser-assisted electric pulse merged devices.

High sensitive position-dependent photodetection observed in Cu-covered Si nanopyramids

Silicon nanopyramids with the excellent ability of light absorption have been mostly reported in solar cells. Here, we report an obviously enhanced lateral photovoltaic effect (LPE) in copper-nanoparticle-covered random Si nanopyramids (Cu@Si-pyramid). Remarkable photoelectric responses are achieved in broadband from 405 to 780 nm. Furthermore, a prominent LPE is double-enhanced from 74.0 to 157.9 mV mm^-1 when the linear region decreases from 3 to 1 mm. Finite-difference time-domain simulation is applied to investigate the origin of the exceptional results. This work declares a position-sensitive property of Si-nanopyramid systems and proposes promising applications to photodetections based on LPE.

Ultrahigh, Ultrafast, and Self-Powered Visible-Near-Infrared Optical Position-Sensitive Detector Based on a CVD-Prepared Vertically Standing Few-Layer MoS2/Si Heterojunction

MoS2, as a typical transition metal dichalcogenide, has attracted great interest because of its distinctive electronic, optical, and catalytic properties. However, its advantages of strong light absorption and fast intralayer mobility cannot be well developed in the usual reported monolayer/few-layer structures, which make the performances of MoS2-based devices undesirable. Here, large-area, high-quality, and vertically oriented few-layer MoS2 (V-MoS2) nanosheets are prepared by chemical vapor deposition and successfully transferred onto an Si substrate to form the V-MoS2/Si heterojunction. Because of the strong light absorption and the fast carrier transport speed of the V-MoS2 nanosheets, as well as the strong built-in electric field at the interface of V-MoS2 and Si, lateral photovoltaic effect (LPE) measurements suggest that the V-MoS2/Si heterojunction is a self-powered, high-performance position sensitive detector (PSD). The PSD demonstrates ultrahigh position sensitivity over a wide spectrum, ranging from 350 to 1100 nm, with position sensitivity up to 401.1 mV mm-1, and shows an ultrafast response speed of 16 ns with excellent stability and reproducibility. Moreover, considering the special carrier transport process in LPE, for the first time, the intralayer and the interlayer transport times in V-MoS2 are obtained experimentally as 5 and 11 ns, respectively.

Size-dependent magnetic tuning of lateral photovoltaic effect in nonmagnetic Si-based Schottky junctions

In this article, we report a magnetic tuning lateral photovoltaic effect (LPE) in a nonmagnetic Si-based Schottky junctions. In the magnetic field intensity range of 0 to 1.6 T, the variation amplitude of LPE sensitivity is as high as 94.8%, the change of LPV is and the change rate of lateral photo-voltage even reaches 520 mV/T at 1.5 T, which is apparently higher than the results of previous reported researches in magnetic materials. This effect is attributed to the combined result of the influence of magnetic field on diffusion current and the rectification property of our anisotropic structure. This work may expand the application of LPE in magnetism field such as magnetic sensor and magnetoresistance, and it suggests a new way to investigate the carrier transport in Schottky junctions under magnetic field.