Synergistic effects of the total ionizing dose （TID） on the single event upset （SEU） sensitivity in static random access memories （SRAMs） were studied by using protons. The total dose was cumulated with high flu...Synergistic effects of the total ionizing dose （TID） on the single event upset （SEU） sensitivity in static random access memories （SRAMs） were studied by using protons. The total dose was cumulated with high flux protons during the TID exposure, and the SEU cross section was tested with low flux protons at several cumulated dose steps. Because of the radiation-induced off-state leakage current increase of the CMOS transistors, the noise margin became asymmetric and the memory imprint effect was observed.展开更多
We report on the temperature dependence of single-event upsets in the 215–353 K range in a 4M commercial SRAM manufactured in a 0.15-lm CMOS process,utilizing thin film transistors. The experimental results show that...We report on the temperature dependence of single-event upsets in the 215–353 K range in a 4M commercial SRAM manufactured in a 0.15-lm CMOS process,utilizing thin film transistors. The experimental results show that temperature influences the SEU cross section on the rising portion of the cross-sectional curve(such as the chlorine ion incident). SEU cross section increases 257 %when the temperature increases from 215 to 353 K. One of the possible reasons for this is that it is due to the variation in upset voltage induced by changing temperature.展开更多
Experimental evidence is presented relevant to the angular dependences of multiple-bit upset （MBU） rates and patterns in static random access memories （SRAMs） under heavy ion irradiation. The single event upset （...Experimental evidence is presented relevant to the angular dependences of multiple-bit upset （MBU） rates and patterns in static random access memories （SRAMs） under heavy ion irradiation. The single event upset （SEU） cross sections under tilted ion strikes are overestimated by 23.9%-84.6%, compared with under normally incident ion with the equivalent linear energy transfer （LET） value of 41 MeV/（mg/cm2）, which can be partially explained by the fact that the MBU rate for tilted ions of 30° is 8.5%-9.8% higher than for normally incident ions. While at a lower LET of - 9.5 MeV/（mg/cm2）, no clear discrepancy is observed. Moreover, since the ion trajectories at normal and tilted incidences are different, the predominant double-bit upset （DBU） patterns measured are different in both conditions. Those differences depend on the LET values of heavy ions and devices under test. Thus, effective LET method should be used carefully in ground-based testing of single event effects （SEE） sensitivity, especially in MBU-sensitive devices.展开更多
Single event upsets(SEUs) induced by heavy ions were observed in 65 nm SRAMs to quantitatively evaluate the applicability and effectiveness of single-bit error correcting code(ECC) utilizing Hamming Code.The results s...Single event upsets(SEUs) induced by heavy ions were observed in 65 nm SRAMs to quantitatively evaluate the applicability and effectiveness of single-bit error correcting code(ECC) utilizing Hamming Code.The results show that the ECC did improve the performance dramatically,with the SEU cross sections of SRAMs with ECC being at the order of 10^(-11) cm^2/bit,two orders of magnitude higher than that without ECC(at the order of 10^(-9) cm^2/bit).Also,ineffectiveness of ECC module,including 1-,2- and 3-bits errors in single word(not Multiple Bit Upsets),was detected.The ECC modules in SRAMs utilizing(12,8) Hamming code would lose work when 2-bits upset accumulates in one codeword.Finally,the probabilities of failure modes involving 1-,2- and 3-bits errors,were calcaulated at 39.39%,37.88%and 22.73%,respectively,which agree well with the experimental results.展开更多
器件特征尺寸的减小带来单粒子多位翻转的急剧增加,对现有加固技术带来了极大挑战.针对90 nm SRAM(static random access memory,静态随机存储器)开展了中高能质子入射角度对单粒子多位翻转影响的试验研究,结果表明随着质子能量的增加,...器件特征尺寸的减小带来单粒子多位翻转的急剧增加,对现有加固技术带来了极大挑战.针对90 nm SRAM(static random access memory,静态随机存储器)开展了中高能质子入射角度对单粒子多位翻转影响的试验研究,结果表明随着质子能量的增加,单粒子多位翻转百分比和多样性增加,质子单粒子多位翻转角度效应与质子能量相关.采用一种快速计算质子核反应引起单粒子多位翻转的截面积分算法,以Geant4中Binary Cascade模型作为中高能质子核反应事件发生器,从次级粒子的能量和角度分布出发,揭示了质子与材料核反应产生的次级粒子中,LET(linear energy transfer)最大,射程最长的粒子优先前向发射是引起单粒子多位翻转角度相关性的根本原因.质子能量、临界电荷的大小是影响纳米SRAM器件质子多位翻转角度相关性的关键因素.质子能量越小,多位翻转截面角度增强效应越大;临界电荷的增加将增强质子多位翻转角度效应.展开更多
基金supported by the Open Foundation of State Key Laboratory of Electronic Thin Films and Integrated Devices,China(Grant No.KFJJ201306)
文摘Synergistic effects of the total ionizing dose （TID） on the single event upset （SEU） sensitivity in static random access memories （SRAMs） were studied by using protons. The total dose was cumulated with high flux protons during the TID exposure, and the SEU cross section was tested with low flux protons at several cumulated dose steps. Because of the radiation-induced off-state leakage current increase of the CMOS transistors, the noise margin became asymmetric and the memory imprint effect was observed.
基金the National Natural Science Foundation of China(No.11405275)
文摘We report on the temperature dependence of single-event upsets in the 215–353 K range in a 4M commercial SRAM manufactured in a 0.15-lm CMOS process,utilizing thin film transistors. The experimental results show that temperature influences the SEU cross section on the rising portion of the cross-sectional curve(such as the chlorine ion incident). SEU cross section increases 257 %when the temperature increases from 215 to 353 K. One of the possible reasons for this is that it is due to the variation in upset voltage induced by changing temperature.
基金supported by the National Natural Science Foundation of China(Grant Nos.11179003,10975164,10805062,and 11005134)
文摘Experimental evidence is presented relevant to the angular dependences of multiple-bit upset （MBU） rates and patterns in static random access memories （SRAMs） under heavy ion irradiation. The single event upset （SEU） cross sections under tilted ion strikes are overestimated by 23.9%-84.6%, compared with under normally incident ion with the equivalent linear energy transfer （LET） value of 41 MeV/（mg/cm2）, which can be partially explained by the fact that the MBU rate for tilted ions of 30° is 8.5%-9.8% higher than for normally incident ions. While at a lower LET of - 9.5 MeV/（mg/cm2）, no clear discrepancy is observed. Moreover, since the ion trajectories at normal and tilted incidences are different, the predominant double-bit upset （DBU） patterns measured are different in both conditions. Those differences depend on the LET values of heavy ions and devices under test. Thus, effective LET method should be used carefully in ground-based testing of single event effects （SEE） sensitivity, especially in MBU-sensitive devices.
基金Supported by the National Natural Science Foundation of China(Nos.11079045 and 11179003)the Important Direction Project of the CAS Knowledge Innovation Program(No.KJCX2-YW-N27)
文摘Single event upsets(SEUs) induced by heavy ions were observed in 65 nm SRAMs to quantitatively evaluate the applicability and effectiveness of single-bit error correcting code(ECC) utilizing Hamming Code.The results show that the ECC did improve the performance dramatically,with the SEU cross sections of SRAMs with ECC being at the order of 10^(-11) cm^2/bit,two orders of magnitude higher than that without ECC(at the order of 10^(-9) cm^2/bit).Also,ineffectiveness of ECC module,including 1-,2- and 3-bits errors in single word(not Multiple Bit Upsets),was detected.The ECC modules in SRAMs utilizing(12,8) Hamming code would lose work when 2-bits upset accumulates in one codeword.Finally,the probabilities of failure modes involving 1-,2- and 3-bits errors,were calcaulated at 39.39%,37.88%and 22.73%,respectively,which agree well with the experimental results.
文摘器件特征尺寸的减小带来单粒子多位翻转的急剧增加,对现有加固技术带来了极大挑战.针对90 nm SRAM(static random access memory,静态随机存储器)开展了中高能质子入射角度对单粒子多位翻转影响的试验研究,结果表明随着质子能量的增加,单粒子多位翻转百分比和多样性增加,质子单粒子多位翻转角度效应与质子能量相关.采用一种快速计算质子核反应引起单粒子多位翻转的截面积分算法,以Geant4中Binary Cascade模型作为中高能质子核反应事件发生器,从次级粒子的能量和角度分布出发,揭示了质子与材料核反应产生的次级粒子中,LET(linear energy transfer)最大,射程最长的粒子优先前向发射是引起单粒子多位翻转角度相关性的根本原因.质子能量、临界电荷的大小是影响纳米SRAM器件质子多位翻转角度相关性的关键因素.质子能量越小,多位翻转截面角度增强效应越大;临界电荷的增加将增强质子多位翻转角度效应.
