| Transition metal trichalcogenides（TMTCs）have become a hot research material for new nanoscale electronic and optoelectronic devices due to their excellent optoelectronic properties,high carrier mobility,large light absorption coefficient,strong anisotropy,and tunable bandgap,among other unique physical properties.Hafnium-doped Zr S3,as an important member of the transition metal trichalcogenides,possesses outstanding anisotropic photoelectric properties due to its anisotropic effective electron mass.Additionally,the exploration of its ferroelectric properties by regulating the oxidation of hafnium-doped Zr S3 further expands its application field.The main research content of this article is as follows:1.We investigated the photoelectric detection properties of ZrS3-based compounds.Firstly,the basic characterization of Zr S3 crystals was carried out to confirm the high crystal quality of the grown Zr S3.The exploration of optical absorption spectra,Raman spectra,and photoelectric current polarization behavior demonstrated consistent optical and photoelectric anisotropic behavior of Zr S3.Zr S3exhibited excellent photoelectric response and wavelength-dependent photoelectric current anisotropy under irradiation of light sources with different wavelengths.Additionally,we tested the gate voltage control performance of the Zr S3 detector,which showed anisotropic and gate voltage-dependent response time and a photoelectric current polarization ratio of up to 1.99 when the gate voltage was-80 V.Hf0.5Zr0.5S3exhibited similar properties to Zr S3.2.We explored a method of preparing Hf0.5Zr0.5O2 by oxidizing Hf0.5Zr0.5S3 and obtained a good oxidation process.The ferroelectric properties of Hf0.5Zr0.5O2 were characterized using techniques such as second harmonic generation,piezoresponse force microscopy,and Kelvin probe microscopy.Significant second harmonic signals and switchable ferroelectric polarization were observed,and potential differences of approximately 0.46 V were observed in different polarization regions,confirming the ferroelectricity of Hf0.5Zr0.5O2.3.We fabricated a graphene/Hf0.5Zr0.5O2/metal ferroelectric tunnel junction and tested the electrical parameters of the device,including I-V characteristics,state retention,and cycling endurance.The device exhibited a tunneling electroresistance ratio greater than 102 and 103 after 100 s and 105 cycles,respectively,explaining the mechanism behind the high tunneling electroresistance ratio.The main tunneling mechanism of the device was investigated through low-temperature I-V characteristic testing. |
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