The Dose Rate Effect Of Domestic Typical Bipolar Transistor Under The High Total Dose

A recent conference report of RADECS pointed out that the total dose of Europa has reached 300krad(Si).With the development of deep space exploration today,long-lifetime and highly reliability satellites gradually become the main trend.According to the project need,the previous research on the radiation effects of the device was mainly concentrated in the low total dose range,while the long-lifetime satellite at higher total dose is more serious,which brings great hidden trouble to the reliability of electronic systems in the aerospace field.With the further exploration of outer space in China,and in order to accelerate the nationalization of electronic components and self-controllable processes,this article will study the dose-rate effects of domestic bipolar transistors at the high total dose 200krad(Si)and ultra-low dose <0.01rad(Si)/s.This study includes the three aspects:First,at higher total doses,the difference in ionizing radiation damage between domestic bipolar transistors under different bias conditions is related to the irradiation bias conditions.Therefore,two PNPs and two NPNs are used in this paper.The transistor was radiated under three different bias conditions.The results show that irradiation bias conditions have a great influence on the ionization damage of domestic bipolar transistors under high total doses,and the damage is greater than zero-bias damage while the base-emitter junction is reversed,and the damage is minimal under positive-polarity.Combining the fringe electric field and the applied electric field,the influence of the bias on the radiation effect is explained in depth.On the other hand,in order to study the enhanced low dose rate damage effect of domestic bipolar transistors,this article still chooses the above four devices to perform irradiation tests at high and low dose rate.The results showed that four kinds of domestic bipolar transistors in the space at low dose rate damaged than the same conditions at the high dose rate when irradiated to a maximum total ionizing doselevel of 200krad(Si)and exhibit enhanced low dose rate sensitivity.When the cumulative total dose reaches 180krad(Si),the NPN bipolar transistor shows damage recovery.According to the bimolecular model,the physical mechanism of the enhanced low dose rate damage effect of domestic bipolar transistors was discussed.Finally,for some bipolar devices,the dose rate response did not appear to be saturated while irradiated at 0.01rad(Si)/s.The radiation damage was increasing with the decrease of the dose rate.But due to the test rotation and cost are too large,this paper only focuses on four bipolar transistors under the floating condition while irradiated at ultra-Low dose rates.The results showed that as the dose rate decreased,there was no saturation trend in the dose rate response.Some devices exhibited significant ELDRS effects when the dose rate dropped to a sufficiently low value.The different device's dose rate saturation trends are different,which may be related to the device's process and circuit design.In summary,this article combines international hotspots,starting from the needs of engineering applications,to conduct research on ionizing radiation effects within a high total dose range and being irradiated at ultra-Low dose rates for domestic bipolar transistors.The research results not only analyzed the influence of bias condition and dose rate on ionization damage,but also discussed the enhanced low dose rate damage effect of the domestic bipolar transistor under high total dose,providing theoretical guidance for device designer and production units.Meanwhile,the radiation effect of domestic bipolar transistors at ultra-Low dose rates was preliminarily explored.