Cyrogenic And Radiation Effects Of SiC JBS Diodes With FGR Structure

Due to its wide band gap and high atomic critical displacement energy,silicon carbide devices have strong ability to resist electromagnetic wave shock and radiation damage,and have great application prospects in space extreme environment.Therefore,the research on damage behavior of silicon carbide based devices in space extreme environment is very important for its application in space extreme environment.In this paper,we take the terminal as the field limiting ring structure silicon carbide Junction Barrier Schottky diode as the device under test,through the 1Me V electron irradiation and ultra-low temperature experimental research combined with TCAD simulation study,based on the characterization of defects and electrical performance degradation of silicon carbide Junction Barrier Schottky diode,reveals the extreme low temperature and electron radiation damage effect and mechanism of silicon carbide Junction Barrier Schottky diode,and establishes the space radiation damage effect model of silicon carbide Junction Barrier Schottky diode based on defect evolution law.The effects of 1Me V electron irradiation on the electrical properties and defect evolution of 4H-SiC JBS diodes are studied.The results show that the I-V and C-V characteristics of 4H SiC JBS diode are damaged by electron irradiation.The main reason is that the defects are produced during the process of electron irradiation,and traps are formed and carriers are trapped.The evolution of defects before and after electron irradiation was analyzed by photoluminescence and deep level transient spectra.The analysis of photoluminescence spectrum shows that there is quenching effect in the process of irradiation,and the defect concentration increases with the fluence of irradiation.The results of deep level transient spectrum analysis show that the carbon vacancy(VC)increases with the increase of irradiation dose.The generation of defects and the increase of their concentration lead to the degradation of electrical properties.The change of electrical properties of 4H-SiC JBS diode at extreme low temperature was studied.The research shows that the change of temperature will change the electrical performance.The inhomogeneous distribution of the transverse barrier in 4H-SiC JBS diodes at 160-292 K is explained by the Gaussian distribution model.The low temperature data below 160 K does not conform to the Gaussian distribution model,and the experimental results at low temperature will be further explained later.The low temperature electron irradiation effect of 4H-SiC JBS diode is simulated.The effects of displacement defect,interface charge,displacement defect and interface charge synergy on the electrical properties of 4H-SiC JBS diode are simulated.Through the simulation of the electrical characteristics at 200 K and 300 K,the conductive mechanism is analyzed.The simulation results of 4H-SiC JBS diode low temperature radiation effect are analyzed.The simulation results of low temperature electron radiation effect are the superposition of the simulation results of electron radiation effect and low temperature effect.