Wavelength Detector Based On Graphene/Thin Si/Graphene

As an important part of image system,wavelength detector has been widely used in artificial intelligence system,security protection,optical communication and safe driving.The traditional wavelength detector preparation process is cumbersome,the detection range is narrow,the accuracy is not high,the application of optical communication has certain limitations,so this paper with graphene(Gr)/thin silicon/Gr prepared a wide range wavelength detector.Specific research content is as follows:1.The light absorption rate and photogenic carrier yield in 40?m thin silicon wafers are simulated using Technology Computer Aided Design(TCAD).The results show that only the first device or even the surface absorbs light for short wavelength light,while for long wavelength light,the first device and even the second device absorb it.2.A photodetector based on 20?m Gr/thin silicon/Gr was constructed.Electrical tests show that the device has a good light response in the visible-near-infrared wide band and the maximum light response to the incident light of about 660 nm,with a response of 50.46 m A/W,compared to the detector rate of 1.49×10¹² Jones,and an external quantum efficiency of 35%.The device is less responsive at 810 nm than the 500?m silicon-based photodetector,and combined with TCAD simulation,we believe this is due to the weak absorption of incident light from 20?m thin silicon to near-infrared areas.3.Two Gr/thin silicon/Gr photodetectors are stacked vertically to build a highly sensitive wavelength detector that accurately determines the incident light wavelength in the 265-1050 nm range.By fitting,the relationship between the wavelength of incident light and the current ratio and intensity of the two devices is obtained,and the analysis shows that the calculated average Root Mean Squared Error(RMSE)of wavelength and actual wavelength is less than 5 nm,and the relative error is about±1.5%,significantly higher than the previously reported wavelength detector.These results suggest that this wavelength detectors may find potential applications in future optoelectronic systems.