Study On Reliability Of Irradiation Effect Of SOI FinFET

The development of microelectronic materials and device architectures in recent years has opened up a new era of devices and circuits.With the deployment of state-of-the-art technology in military and space applications,the radiation resistance of advanced technologies is worrying.The nature of the material determines the carrier lifetime,transport and defect kinetics in the integrated circuit,and the geometry and doping of the device have a large effect on the radiation-induced trapped charge,lifetime degradation,and leakage current in the device.There are still many challenges in the semiconductor industry's development of tracking Moore's Law below the 28 nm node.Among them,SOI Fin FET has been used as a promising alternative to meet the challenges of continued scale-up.The SOI Fin FET has the advantages of high channel migration speed and low power consumption,and also reduces various parasitic transistor effects between the substrate and the source and drain active regions.Although the performance of SOI Fin FET devices is superior,the ability to resist radiation is greatly compromised due to the presence of buried oxides.The goal of this paper is to understand how SOI Fin FET devices react to radiation and analyze the factors that affect the SOI Fin FET radiation response.Firstly,the Silvaco TCAD software was used to build the SOI Fin FET device model and initially calibrate the accuracy of the model.Then the effects of the total dose effect of different doses on the subthreshold characteristics and threshold voltage of Fin FET devices are analyzed.It can be obtained through simulation that the larger the irradiation dose,the more severe the degradation of subthreshold characteristics and the more negative the threshold voltage drifts.Then the distribution of the potential of the Fin FET device with different Fin width and channel length under the total dose effect is analyzed.The results show that the larger the Fin width,the larger the threshold voltage drift at the total dose,for the narrow Fin type device.It has stronger radiation resistance than wide Fin.Devices with shorter channel lengths produce higher threshold voltage offsets and leakage currents.Finally,the simulation of the device under single-particle irradiation shows that the larger the drain bias,the larger the drain doping concentration,the larger the incident single-particle LET value,the larger the transient pulse current at the drain end,and the device source is found.The vicinity of the drain junction depletion region and the lower gate region are sensitive to single-particle effects.Then,the experimental study studied the influence of different device size structures on the basic electrical characteristics of the device,and obtained the relationship between the subthreshold characteristics of the basic electrical characteristics and threshold voltage of the device and the device structure parameters: Fin fin width is large,side gate to channel capability The weaker,the subthreshold characteristics of the device will be worse.When the Fin fin width is smaller,the subthreshold characteristics of the device are better.The smaller the channel length,the smaller the threshold voltage and the larger the transconductance,but the shorter the short channel effect.Severe;while the number of Fin increases,the subthreshold characteristics and leakage current characteristics deteriorate,but the maximum transconductance increases.Finally,the experimental study investigated the effect of different device structure sizes on the degradation of the electrical parameters of the device under total dose radiation: when the Fin fin width is small,the device can well control the surface potential of the Si-BOX and eliminate the back-grid capture.The charge has a better anti-radiation effect on the front gate potential in the vertical direction.When the channel length is small,the device leakage current is larger,but the gate-to-channel control ability is also stronger;the number of Fin increases.At this time,the threshold voltage is more degraded,but the maximum transconductance degradation is relatively small.Finally,according to the principle of total dose irradiation,some optimization methods are proposed in the process and structure of the device to achieve the effect of resisting total dose radiation.