Preparation And Performance Of Two-dimensional MoS₂ Electric Double-layer Transistor Based On PEO/LiClO₄ Solid Electrolyte

The transition metal chalcogenides(TMDs)have an adjustable band gap of 1-2eV,and can be used to construct field-effect transistors with a high switching ratio to achieve their applications in the fields of photoelectric detection and information storage.However,due to the limitations of Coulomb impurity scattering,polar surface optical phonon scattering and charge traps,the carrier mobility of actual transistor devices is much lower than its theoretical value,limiting the size of its on-state current,thereby reducing the device Switch ratio.Ion-conducting solid electrolyte as the gate dielectric of the transistor can suppress the coulomb impurity scattering of the channel,improve the carrier mobility,and form an electric double layer capacitor to enhance the gate control effect,thereby greatly improving the operating voltage of the transistor and switch ratio and other characteristics.However,when the transistor with the solid electrolyte as the gate dielectric is applied to multiple devices on the same substrate,there is the problem of mutual interference between the de vices.We use electron beam to irradiate po lyethylene oxide(PEO)to make it denatured and insoluble in water to pattern it,and using PEO/LiC l O₄ solid electrolyte as the gate dielectric to build an electric double layer transistor based on TMDs material,explore its preparation process,and on the basis of this study device performance,the main content is as follows:(1)MoS₂ was used as the channel material,and PEO/LiC l O4 solid electrolyte was used as the gate dielectric to construct the electric double layer transistor.The device is dried at a low temperature by freeze drying to solve the problem of electrode corrosion caused by excessively high drying temperature..Electrical tests on transistors have shown that using solid electrolyte as the gate dielectric can significantly improve the channel conductance(?10³)and electron mobility of the device,making the switching ratio of the device reach 10⁵.Based on photoluminescence spectroscopy(PL)analysis,the improvement in device performance is due to the shielding effect of the solid electro lyte on defects and the effect of charge injection on the channel.The difference in mobility calculations indicates that capacitive coupling can significantly affect the gate field effect control effect.(2)Based on the improvement of the performance of MoS₂ transistor devices by PEO/LiC l O₄ solid electrolyte,a semi-channel-coupled transistor(PEO/LiC l O₄ solid electrolyte covers half of the device channel)using MoS₂(N-type)and WSe₂(P-type)as a channel material through a photoresist process(based on electron beam exposure).For MoS₂ transistors,the on-state conductance is mainly affected by the source gate contact barrier,and the ion gate improves the contact between the device drain gate and the semiconductor,resulting in saturation of the device's ion gate transfer characteristic curve.For WSe₂ transistors,the on-state conductance of the device is mainly affected by the drain gate contact barrier.As the gate voltage injects carriers into the channel and regulates the contact barrier,,the outp ut characteristic curve of the device presents three intervals when V_ig>0 V,namely reverse conduction region,middle cutoff region and forward conduction region.