Study Of Quantum Dot Field Effect Transistor Photodetectors Based On Graphene Perovskite

Since 2004,graphene was stripped from highly directed pyrolytic graphite by British scientists.It has been widely used in semiconductor electronics,material science and other fields due to its outstanding electrical,mechanical and optical properties.Graphene has high carrier mobility,good mechanical and thermal conductivity.The transmittance coefficient of single graphene to light is up to 97.7%,and it can absorb the wide spectrum range of visible light to terahertz band.Therefore,graphene has broad application prospects in uncooled,wide spectrum,high responsivity and ultrafast photoelectric detection.However,thanks to the small optical absorption coefficient and the absence of gain mechanism,graphene based photodetectors can not achieve high detection performance.Amorphous metal-halide perovskite materials have attracted extensive attention due to their high optical absorption coefficient,long carrier diffusion length and excellent carrier characteristics.In view of the problem of single graphene photodetectors,this paper combines graphene with perovskite materials to solve the above problems.In this paper,the preparation and properties of graphene field-effect structure photoelectric detector are first studied.In this paper,plasma enhanced chemical vapor deposition(CVD)was used to obtain the thin films of graphene on the insulating substrate,and then used for the preparation of graphene photoelectric detection devices.The morphology,thickness and square resistance of graphene films were characterized by scanning electron microscopy,Raman spectroscopy and Holzer effect tester.Secondly,the photoelectric properties of graphene photoelectric detection devices are tested and analyzed by using 400nm laser light source.The bipolar curves are obtained,and the factors affecting the electrical properties of graphene,such as silicon dioxide substrate material,film material surface doping,and the factors affecting the electrical properties of graphene,are obtained.The contact of metal/graphene is analyzed.At the same time,the optical properties,photocurrent generation and optical properties of graphene were also analyzed and studied.At the same time,the optical performance of the device is tested and analyzed.In the end,the preparation and performance of the graphene/perovskite quantum dot composite photoelectric detector are studied.The preparation of the graphene/perovskite quantum dot composite photodetector,the working principle of the device and the performance of the device are mainly introduced.The I-V curve and the I-t curve under the light of the device are obtained.Through the test and analysis,it is confirmed that the composite photodetector has high responsiveness and stability.Under the light of 400nm wavelength,the maximum current of 12 uW is 64?A,and the response rate is 6.4 A/W.The corresponding photoconductivity gain and detection rate are 3.7×10~4?6×10~7 Jones respectively.