Research On Polarization Flip Characteristics And Polarization Induced Enhancement 2DEG Characteristics Based On FE/SC Junction

This thesis mainly studies the factors that affect the electrical properties of ferroelectric field effect transistors and negative capacitance field effect transistor,and the optimization effect of gallium oxide on the electrical properties of ferroelectric field effect transistors and negative capacitance field effect transistor.In addition,a high electron mobility transistor（HEMT）based on ferroelectric polarization charge induced two-dimensional electron gas（2DEG）is studied,and the electrical characteristics of FE/Ga N based high electron mobility transistor and FE/ε-Ga₂O₃ based HEMT are compared.The research results are as follows:In this thesis,the ferroelectric/semiconductor（FE/SC）capacitor structure model is studied.By changing the model parameters of ferroelectric polarization,semiconductor doping concentration and material thickness,the surface potential of semiconductor is simulated.The results show that the surface potential of ferroelectric capacitor decreases with the increase of ferroelectric remanent polarization（P_r）,ferroelectric coercive field（E_c）,semiconductor doping concentration and thickness,and increases with the increase of ferroelectric thickness.The model structure of ferroelectric field effect transistor is studied,and the hysteresis loop and transfer characteristics are obtained by studying.The results show that the larger the ferroelectric remanent polarization and the ferroelectric coercive field,the wider the memory window width of the ferroelectric field effect transistor.The smaller the ferroelectric dielectric constant is,the wider the memory window of the ferroelectric field effect transistor is.FE/ε-Ga₂O₃ based ferroelectric field effect transistor exhibit better electrical properties than FE/Si based ones.The device structure models of Fe/Ga N based HEMT and FE/ε-Ga₂O₃ based HEMT are established.The transfer characteristics,output characteristics,interfacial carrier concentration and potential well depth are simulated by changing the ferroelectric saturation polarization and remanent polarization.The results show that the increase of ferroelectric saturation polarization and remanent polarization can increase the carrier concentration of 2DEG.Gallium nitride based HEMT will affect the performance of 2DEG when the gate voltage is too large.Compared with FE/Ga N,FE/ε-Ga₂O₃based HEMT have more stable 2DEG performance.