功率VDMOS器件的SEB致SEGR效应研究

功率VDMOS器件是航天器电源系统配套的核心元器件之一,在重粒子辐射下会发生单粒子烧毁(SEB)和单粒子栅穿(SEGR)效应,严重影响航天器的在轨安全运行。本文在深入分析其单粒子损伤机制及微观过程的基础上,发现了功率VDMOS器件在重粒子辐射下存在SEBIGR效应,并在TCAD软件和¹⁸¹Ta粒子辐射试验中进行了验证。引起该效应的物理机制是,重粒子触发寄生三极管,产生瞬时大电流,使得硅晶格温度升高,高温引起栅介质层本征击穿电压降低,继而触发SEGR效应。SEBIGR效应的发现为深入分析功率MOSFET器件的单粒子辐射效应奠定了理论基础。

Research on SEB Induced SEGR Effect of Power VDMOS Device

Power VDMOS is one of the key devices in spacecraft power supply systems. Under the radiation of heavy particles, single event burnout (SEB) and single event gate-rupture (SEGR) effects will occur, which have a serious impact on the safe operation of spacecraft in orbit. Based on the deep analysis of the single event damage mechanism and micro process, it was discovered that there was a SEBIGR effect in power VDMOS under heavy particle radiation, which was verified by TCAD software and ¹⁸¹Ta particle radiation test. The physical mechanism of the effect was that the temperature of the silicon lattice was increased by the instantaneous large current generated by the heavy particles triggering the parasitic bipolar transistor, and the intrinsic breakdown voltage of the gate dielectric layer was reduced by the high temperature, then the SEGR effect was triggered. The discovery of SEBIGR effect layed a theoretical foundation for the further analysis of the single particle radiation effect of power MOSFETs.