The Research On Metal Oxide Semiconductor-Perovskite High Performance Photodetector

Organic-inorganic hybrid perovskite materials have been widely used in solar cells and photodetectors due to their long carrier diffusion length,wide light absorption,and small exciton binding energy.And optoelectronic devices such as light-emitting diodes.However,the low conductivity of perovskite materials and the low stability caused by degradation of perovskite materials in contact with moisture are still the focus of current research.In this paper,a newly developed two-step ligand exchange method is used to obtain a regular perovskite quantum well and combine it with a metal oxide semiconductor film to design a highly sensitive and stable method on a flexible substrate.A phototransistor of a quasi-two-dimensional perovskite-indium gallium zinc oxide film heterostructure.This paper mainly carried out the following aspects of research,the research results are as follows:1.The metal oxide semiconductor film was prepared by RF magnetron sputtering.The metal oxides prepared under different conditions of temperature,background pressure,sputtering power,working pressure and working time were systematically studied.The microstructure and transistor characteristics of the semiconductor film.The experimental results show that we have prepared a high performance indium gallium zinc oxide thin film transistor by adjusting the parameters.The device has a threshold voltage of about-0.5V,a mobility of up to 44.93 cm²/Vs,and a good I_on/offn/off ratio of 10⁸.2.A two-dimensional perovskite film was prepared based on one-step precursor solution spin coating method,and its morphological characteristics and sample composition were analyzed.The experimental results show that the synthesized two-dimensional perovskite film has a smooth surface and a roughness of about 8.7 nm.We used X-ray diffraction spectrometer to measure the crystal orientation of the two-dimensional perovskite film of the vegetation,and measured the diffraction peaks?111,202?of two distinct perovskite components,which are located at 2?of 14.2°and Around 28.5°,this is consistent with the peak position of the two-dimensional perovskite XRD characterization in the published literature,and the full width at half maximum of the peak in the entire XRD pattern indicates good crystallinity.Through the test of its photoluminescence spectrum and absorption spectrum,it is found that the two-dimensional perovskite phase is distributed according to a certain regularity.The photoluminescence peak of the crystal continuously changes from 760 nm to 580 nm,and the corresponding light absorption peak also changes from 740 nm to 580 nm.3.A regular quasi-two-site heterogeneous perovskite quantum well was prepared based on the newly developed two-step ligand exchange method,and further covered with a metal oxide film?IGZO?to produce PET/RF TIO/ALD Al2O3/quasi-2D perovskites/IGZO/Cr/Au structure perovskite phototransistor devices.At the same time,the electrical properties of the device were characterized by Keithley 4200 and 2912semiconductor analyzers,and the morphology and composition of the device were characterized.The experimental results show that the device has an excellent optical response value of>105 A/W at 457 nm and a wide-band photorefractive response?457-1064 nm?.By operating the device in a depleted state,a specific detection rate of5.1 x 1016 Jones was found,which is the highest recorded value of all perovskite-based photodetectors reported to date.In addition,the infrared storage of the device maintains a constant resistance state and hardly relaxes in 104 seconds.Furthermore,covering the perovskite with an oxide film results in a phototransistor structure that prevents moisture penetration and significantly improves device stability.