Study On The Sensitive Position And Damage Mechanism Of Strong Electromagnetic Pulse In MOS Devices

With the gradual reduction of the feature size of semiconductor devices and the continuous improvement of integrated circuit integration,the system and circuit equipment based on semiconductor devices have been applied more and more widely.While the performance of the circuit is gradually improved due to the improvement of integration,the devices and circuits are more vulnerable to external factors such as strong electromagnetic pulse.Every year,the economic losses caused by strong electromagnetic pulse increase,so it is very important to study the sensitive area and damage mechanism of strong electromagnetic pulse on semiconductor devices.Using Sentaurus TCAD device simulation software,a three-dimensional MOSFET device is built and simulated in EMP and HPM environments.Using the advantage of threedimensional structure,the distribution of electric field current and temperature in the device is observed from different angles,and the sensitive position of the device under the influence of strong electromagnetic pulse is found,and the internal mechanism is analyzed.The simulation results show that when EMP signal is injected from the device drain,the electric field near the space charge region of the PN junction in the MOS transistor drain is the most intensive,and the high current is mainly concentrated in the source,drain and the channel directly below the gate.Therefore,the area where the damage and failure occur most easily due to heat accumulation is located near the PN junction in the device drain.Under the same conditions,small-size devices are more vulnerable to thermal damage and failure due to their compact structure and difficult heat diffusion due to the influence of EMP injection.In HPM environment,because of the high frequency of injection signal,the heat generated in the previous cycle can not be completely diffused before the coming of the next cycle.The constant accumulation of heat eventually leads to the phenomenon of thermal damage near the PN junction,and the probability of failure at the drain end is greater than that at the source end because the signal is injected from the drain end.Similarly,under the same conditions,the internal heat of small size devices is easier to accumulate and fail.Through three-view observation and analysis,the heat distribution near the thermal damage failure point is ellipsoidal,and the structure of lightly doped drain can effectively prevent the electric field accumulation at the bend of PN junction,thus to a certain extent,the temperature is not too high to achieve the purpose of strengthening devices.Finally,the methods of strengthening devices are proposed from two aspects of device level and system level.In this paper,the damage location and mechanism of MOS devices under strong electromagnetic pulse are studied and analyzed,which lays a theoretical foundation for the subsequent study of the impact of strong electromagnetic pulse on the device.