Construction method of intelligent thin film photodetector capable of identifying detection wavelength

Abstract

The invention discloses a construction method of an intelligent thin film photodetector capable of identifying the detection wavelength. The method comprises the following steps: (1) firstly, evaporating CdS on an SiO2 / Si substrate and then evaporating ZnS on a CdS thin film; (2) growing graphene on copper foil, coating a copper sheet surface on which the graphene grows with PMMA in a spinning manner, baking the product, putting the product into an FeCl3 solution for etching, after the copper foil is etched, putting a PMMA / graphene thin film into diluted hydrochloric acid and water for cleaning residual FeCl3 etching liquid on the surface respectively, fishing up the PMMA / graphene thin film by an SiO2 / Si substrate coated with the CdS / ZnS thin film, airing the PMMA / graphene thin film and then removing the PMMA by a low-pressure vacuum annealing method; and (3) obtaining a graphene / ZnS / CdS heterojunction thin film on the SiO2 / Si substrate, and depositing 10nm Cr / 100nm of Au by an electron beam vapor deposition method to manufacture an electrode of a device through a mask plate. Semiconductors with different band gaps are compounded, so that ultraviolet light and visible light can be distinguished through a characteristic parameter of response time; and the construction method is simple in process and low in cost and has relatively good practical value.

Description

technical field [0001] The invention belongs to the field of light detection, and in particular relates to a construction method of an intelligent thin-film light detector capable of identifying detection wavelengths. Background technique [0002] Due to their applications in communication, sensing, environmental monitoring, imaging, etc., photodetectors have been extensively studied in recent years. When the photosensitive material is excited by light greater than its band gap energy, hole-electron pairs are generated in the photosensitive material, and the current passing through its external circuit will increase, and this signal can be used as a photodetection. This shows that the wavelength range of light detected by the photosensitive material is determined by its forbidden band width. Therefore, ultraviolet light detectors, visible light detectors, infrared light detectors and other light detectors all need to select photosensitive materials with corresponding band g...

AI Technical Summary

Problems solved by technology

However, when light detection is performed in a real environment, we do not know the intensity of the detected light, so we cannot distinguish the wavelength of the detected light from the obtained photocurrent

In addition, there is no experiment to show that the response time of the photodetector is related to the wavelength of the detected light.