Application Research On FET-Photoelectric Sensor Based On Graphene Nanosheets Embedded Carbon Films

Photoelectric sensors,as neuron components of industrial machines,play an important role in high-speed non-contact information and system response processing.The discovery of new materials and the evolution of preparation methods,the research of photoelectric sensors has continued to make breakthroughs in high precision,fast response,and tunable directions.Among them,Graphene-Si heterojunctions have been favored in the research of optoelectronic heterojunctions mainly due to the excellent electromagnetic,thermodynamic,and optical properties of graphene.However,the photoelectric test performance of this new heterojunction is not outstanding compared with other new materials,the light detection range is only between450 ? 900 nm,and the response rate is at the mA/W.The preparation process and cost are complicated and expensive,which limits the popularity and application of this type of photoelectric sensor.In this study,a series of carbon films with graphene nanosheets embedded vertically were prepared by using the electron irradiation mode in an electron cyclotron resonance plasma system.The van der Waals contact method was used to transfer the film to form a heterojunction with silicon.Two different bias modulation modes are used to study the methods of improving and improving the light guide,photovoltaic and spectral response characteristics of optoelectronic heterojunctions.In this study,an electron irradiation mode in an electron cyclotron resonance plasma system was used to prepare a carbon film containing graphene crystals vertically embedded,and a van der Waals contact was used to transfer the film to form a heterojunction with silicon.Two kinds of devices(1)FET device and(2)vertical power supply device were studied in different bias modulation modes to study the methods of improving and improving the light guide,photovoltaic and spectral response characteristics of the photoelectric heterojunction.The specific results of this study are as follows:(1)TEM micrographs,local electron energy loss spectroscopy analysis,and Raman spectroscopy are used to comprehensively verify that when the substrate deposition bias voltage is 80 V under electron irradiation,the closed magnetron electric field The nanometer-scale carbon film prepared in the electron cyclotron resonance plasma atmosphere has a highly crystallized lamellar graphene vertical embedded structure.The membrane space structure has a highly complex cross-linked edge structure of amorphous carbon and crystalline graphene,and doped electrons are mainly concentrated in this region.(2)Study of 80 V deposition biased graphene vertically embedded carbon film and n-Si heterojunction field effect transistor devices.In lateral bias mode,photogenerated carriers are detached due to lateral electric field due to diffusion in the film.It forms part of the photocurrent and results in extremely high light response rate,up to 1.25 × 104 A / W,the peak wavelength of the response spectrum is 600 nm,and the response rate of the 20 V carbon film with extremely low crystallinity is reached by the mA / W level under the action of a lateral electric field A / W,the spectral peak wavelength shifted to around 810 nm.(3)Research on carbon film / silicon vertical power supply devices.Under vertical reverse bias modulation,the response rate of 80 V carbon film heterojunction devices can reach a maximum of 92.57 A / W,with a response peak around 700 nm.It improves the utilization rate of photo-generated carriers and prolongs the time of carrier recombination.The fastest time response is 4.91 us.The application in the field of weak detection is broadened,and the spectral response range is increased to 450 ? 1100 nm.