Modeling And Simulation Of The Electrical Characteristics In FinFET

With the development of microelectronic technology, the channel length of MOSFET has shrinked to nanoscale level. Power dissipation, short channel effect, and quantum effect have become critical issues which restrict the development of integrated circuits. In order to reduce the power dissipation and suppress the short channel effect, InGaAs FinFET has attracted much attention due to its extraordinary electron mobility which is about one order of mangnitude larger than that of silicon. However, only few works report the electrical characteristics of InGaAs FinFET while there are a tremendous amount of researchs about silicon FinFET.This thesis mainly studies the conduction model in In0.53Ga0.47As nFinFET. In the first chapter, the development of semiconductor device and the status and difficulties in the research of FinFET and InGaAs FET are introduced. In the second chapter, the conduction model in In0.53Ga0.47As FinFET is investigated with the consideration of quantum effect and quasi-ballistic transport. A quantum capacitance model in FinFET is also developed. The third chapter gives the experimental results about the electrical characteristics in In0.53Ga0.47As FinFET. By comparing the simulation results of the developed conduction model with experimental results, the effective mobility of electron and the related scattering parameters are obtained. In the last chapter (Forth chapter), the summary and outlook about this thesis are stated.The main results of this thesis can be summarized as follows:(1) The electrons in the channel of In0.53Ga0.47As FinFET (HFin/WFin=40/40nm) are under volume inversion instead of surface inversion when the gate voltage is largger than threshold voltage. (2) The conduction model and capacitance model are developed based on the multiple subband and quasi-ballistic transport. Then an analytical expression of drain current in terms of gate voltage, source-drain voltage, and temperature is obtained. (3) The effective mobility of electron and related scattering parameters are obtained by comparing the experimental and simulation results. An abnormal phenomenon that the mobility increases with increasing temperature is observed indicating the existence of high density traps in InGaAs/Al2O3 interface.The above results provide us with new knowledge, methods and models for understanding the conductive characteristics in InGaAs/Al2O3 FinFET, and have important scientific and application value for promoting the research and development of InGaAs FinFET.