Graphene/silicon/graphene-based avalanche photodetector and its preparation method

Abstract

The invention discloses a graphene / silicon / graphene-based avalanche photodetector and a manufacturing method thereof. The avalanche photodetector comprises an n-type silicon substrate, a silicon dioxide isolation layer, a silicon dioxide window, a silicon dioxide insulation layer, a top electrode, a graphene interdigital electrode film and an anti-reflection layer. Graphene serves the transparent interdigital electrode and together with the silicon substrate, the photodetector of an MSM-type structure is formed. The photodetector can carry out wide spectrum detection, the problem that the traditional silicon-based PIN junction is low to ultraviolet light detection response can be solved; the anti-reflection layer enhances absorption of incident lights, and photocurrent is enhanced; under the effect of large reverse bias, a strong electric field is generated among the grapheme interdigital electrodes, collision ionization is likely to happen to photocarrier and silicon lattice, and high gain is obtained. The graphene / silicon / graphene-based avalanche photodetector and a manufacturing method thereof have the advantages of high response degree, quick response speed, large internal gain, small switch ratio and low power consumption.

Description

technical field [0001] The invention belongs to the technical field of photoelectric detection, and relates to the structure of a photoelectric detection device, in particular to a graphene / silicon / graphene-based avalanche photodetector and a preparation method thereof. Background technique [0002] Avalanche ultraviolet photodetectors have the advantages of high sensitivity, high optical response, and fast response speed, and have important applications in high-speed modulation and weak signal monitoring. For the silicon-based avalanche photodetector to reach the avalanche condition, a high voltage is required and the power consumption is large. Therefore, there is a need to reduce the voltage at which avalanche conditions are reached. Traditional silicon-based PIN junction ultraviolet detector devices require thermal diffusion or ion implantation processes, and there is a dead layer problem for ultraviolet light, and the response decreases rapidly as the wavelength of the...

AI Technical Summary

Problems solved by technology

Traditional silicon-based PIN junction ultraviolet detectors require thermal diffusion or ion implantation processes, and there is a dead layer problem for ultraviolet light, and the response decreases rapidly as the wavelength of incident light decreases.

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