大電力用半導体デバイスの宇宙線故障率計算手法

Power semiconductor devices are susceptible to catastrophic failures when exposed to energetic particles present in cosmic radiation. The most serious failure mechanism is single event burnout (SEB). SEB in terrestrial operating condition is a widely recognized problem due to the usage of high Power semiconductor devices in many terrestrial applications. However, the recent increase in the aircraft power requirement and subsequent demand for high power semiconductor devices in avionics indicates the importance of expanding SEB study to higher altitudes. Moreover, the SEB failure rate in avionic system is many times higher than terrestrial electronics due to the increase in cosmic ray flux at high altitudes. The calculation of SEB failure rate of power devices plays critical role in power device selection to make the system robust against cosmic radiation. The failure rate calculation using modeling approaches is very easy and offers many advantages compare to real life tests and accelerated tests. However, empirical formula proposed by Zeller from the accelerating testing result can only be applicable to evaluate the failure rate at sea level. In this research, a universal failure calculation method is proposed to evaluate the failure rate of any high power semiconductor device. Unique feature of decoupling between failure cross section and cosmic ray flux spectrum in the proposed method makes it possible to calculate the failure rate in any radiation condition like terrestrial conditions, aviation altitudes, space environment etc. The failure rate results shown for PiN diodes of 100 μm (1) and 300 μm (3) due to the interaction of cosmic ray neutrons up an altitude of 60 km. First chapter provides the basic introduction about purpose of this work, the research objectives and importance of proposed failure rate calculation method. Second chapter describes the origin of radiation along with the radiation environment. The interaction of radiation with the matter and in particular the discovery of Single Event Effects in electronic integrated circuits is discussed. Moreover, we discussed the reason for considering the cosmic ray neutrons in the present work. Third chapter presents the literature review about energetic particle interaction with the high power semiconductor devices. The phenomena leading to device destruction also discussed in various power devices in detail. Fourth chapter describes the Single Event Burnout simulation of PiN diode. The physical process leading to the failure is shown for 300 μm and 100 μm PiN diode using the simulation results. The transient current waveforms are shown to differentiate the burnout and non-burnout situations. Fifth chapter introduces the proposed universal failure rate calculation method. Various components of the failure calculation method are discussed in detail. The threshold charge for device destruction obtained from simulation results is shown for 300 μm and 100 μm PiN diode. Sixth chapter presents results obtain from the proposed method. The calculated failure rate at sea level is validated with the Zeller results. Further, altitude dependent failure rate up to 60 km is obtained using the neutron spectrum from EXPACS database. In addition, the cutoff energy dependence on failure rate also briefly discussed.九州工業大学博士学位論文 学位記番号: 生工博甲第428号 学位授与年月日: 令和4年3月25日1 Introduction|2 Radiation and its effects on Electronics|3 SEB in High power semiconductor devices|4 Simulation of Single Event Burnout phenomena of PiN Diode|5 Proposed Universal SEB Failure rate calculation method|6 Failure rate results|7 Conclusion九州工業大学令和3年

大電力用半導体デバイスの宇宙線故障率計算手法

九州工業大学博士学位論文（要旨）学位記番号：生工博甲第428号 学位授与年月日：令和4年3月25

Extension of Zeller’s Silicon Power Device SEB Failure Rate Calculation method to Aviation Altitude

Power semiconductor devices are susceptible to catastrophic failures when exposed to energetic particles present in cosmic radiation. The most serious failure mechanism is single event burnout (SEB). The calculation of SEB failure rate of power devices plays critical role in power device selection to make the system robust against cosmic radiation. The phenomenological SEB failure rate calculation approach proposed by Zeller is applicable only to terrestrial radiation environment. In this work, altitude dependent parameters are introduced in the Zeller formula to expand the application to higher altitudes by utilizing proposed TCAD based failure rate calculation method results.8th International Symposium on Advanced Science and Technology of Silicon Materials, November 7 - 9, 2022, Okayama, Japan (2020年11月15日～19日開催予定から変更

Altitude dependent failure rate calculation for high power semiconductor devices in aviation electronics

The electric power usage in aircraft has reached 1 MW. Therefore, use of high power semiconductor devices expected to increase in avionics. Single event burnout failure happens when power devices operating in blocking condition interact with the cosmic radiation. The failure rate in power devices is more in airplane altitude compare to terrestrial operation. In this paper, the failure rate of high power silicon PiN diode is evaluated when operating in airplane altitude due to the interaction of cosmic ray neutrons. The proposed formula has the unique feature of decoupling between failure cross section and cosmic ray neutron flux. This makes it possible to calculate the failure rate under any cosmic radiation environment using the proposed failure rate formulation

A TCAD Simulation Study for a New Technique to Calculate Carrier Recombination Lifetime Based on Open Circuit Voltage Decay Method

A new technique for calculation of correct carrier recombination lifetime in intrinsic layer of silicon PiN diode on the basis of the Open Circuit Voltage Decay method was invented. The new technique can remove the effects of carrier diffusion into p+ and n+ layer from intrinsic layer and carrier injection into intrinsic layer from depletion layer. The comparison of calculation results between the conventional and new technique by employing TCAD simulation indicated that the new technique can calculate more correct recombination lifetime value.8th International Symposium on Advanced Science and Technology of Silicon Materials, November 7 - 9, 2022, Okayama, Japan (2020年11月15日～19日開催予定から変更