Optical detector of Van der Waals heterojunction based on two-dimensional indium selenide and black phosphorus and manufacturing thereof

Abstract

The invention relates to the optical detector of a Van der Waals heterojunction based on two-dimensional indium selenide and black phosphorus and manufacturing thereof. The optical detector comprisesa silicon substrate and a silicon dioxide oxide layer arranged on the silicon substrate. A p-type black phosphorus layer is arranged on the silicon dioxide oxide layer. An n-type indium selenide layeris arranged on the p-type black phosphorus layer. The p-type black phosphorus layer and the n-type indium selenide layer form a Van der Waals p-n heterojunction. A drain electrode is arranged on then-type indium selenide layer. A source electrode is arranged on the p-type black phosphorus layer. One surface of the silicon substrate, which is opposite to the silicon dioxide oxide layer, is provided with a gate electrode. In the invention, n-type indium selenide and p-type black phosphorus form the p-n heterojunction; through a built-in electric field at an interface, the rapid separating of electrons and hole carriers can be realized; a carrier composite probability is reduced and then the dark current of a device is deceased; and a detector noise can be reduced and a response speed is increased.

Description

technical field [0001] The invention relates to a photodetector based on a van der Waals heterojunction of two-dimensional n-type indium selenide and p-type black phosphorus and a preparation method thereof, which can realize low noise, high responsivity, fast response and wide spectrum The light detection belongs to the technical field of light detection. Background technique [0002] The ability of a single detector to achieve efficient light detection in a wide spectral range has important application value and has a wide range of applications in many fields, including optical communication, infrared imaging, remote sensing, environmental monitoring, spectral analysis, astronomical detection, etc. In the past, detectors that detect different wavelength bands can only be based on materials with different band gaps. For example, GaN is often used for ultraviolet light detection, Si for visible light detection, InGaAs for near-infrared light detection, and mid-infrared light...

AI Technical Summary

Problems solved by technology

[0004] At present, the two-dimensional semiconductor van der Waals p-n heterojunction mainly faces the following problems: 1) The commonly used two-dimensional layered transition metal chalcogenides (TMDCs) materials are mainly n-type, and the electron mobility is low (electron effective Large mass), low light absorption and luminescence efficiency (single layer is direct band gap, multilayer is indirect band gap), etc., which lead to the failure of the electrical transport performance and photoelectric performance of the heterojunction, which limits its further optimization and improvement; 2) Although some p-type MoS 2 and WSe 2 Such as TMDCs can be achieved by CVD growth doping or electric field regulation, etc., but the introduction of dopant atoms greatly reduces the quality of the material and then reduces the hole mobility, while the electric field regulation increases the complexity of the device, etc.; 3) GaSe outside of TMDCs It is a common p-type semiconductor, but its band gap is greater than 2eV, which limits its application in the visible and near-infrared bands

However, this detector is a photoconductive detector, so it must be driven by an external voltage to achieve work. At the same time, this type of detector tends to have a relatively large dark current compared with p-n junction photovoltaic detectors.

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