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
The protons in the secondary beam in the Beijing Electron Positron Collider（BEPC） are first analyzed and a large proportion at the energy of 50-100 MeV supply a source gap of high energy protons.In this study, the p...The protons in the secondary beam in the Beijing Electron Positron Collider（BEPC） are first analyzed and a large proportion at the energy of 50-100 MeV supply a source gap of high energy protons.In this study, the proton energy spectrum of the secondary beam was obtained and a model for calculating the proton single event upset（SEU） cross section of a static random access memory（SRAM） cell has been presented in the BEPC secondary beam proton radiation environment.The proton SEU cross section for different characteristic dimensions has been calculated.The test of SRAM SEU cross sections has been designed,and a good linear relation between SEUs in SRAM and the fluence was found,which is evidence that an SEU has taken place in the SRAM.The SEU cross sections were measured in SRAM with different dimensions.The test result shows that the SEU cross section per bit will decrease with the decrease of the characteristic dimensions of the device,while the total SEU cross section still increases upon the increase of device capacity.The test data accords with the calculation results,so the high-energy proton SEU test on the proton beam in the BEPC secondary beam could be conducted.展开更多
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.
文摘通过对静态随机存取存储器(static random-access memory,SRAM)单粒子翻转截面的研究,提出了一种更有效、成本更低、可测量一到几十兆电子伏能量范围内中子能谱的新方法。利用已发表单粒子翻转截面信息的SRAM,采用奇异值分解(singular value decomposition,SVD)方法进行解谱,可测试低能中子源的中子能谱。在进一步的研究中,利用信息熵理论研究了SRAM的数量与能谱测试准确性的关系。研究结果表明,解谱结果的精度在很大程度上取决于SRAM翻转截面的敏感区宽度和参与解谱的不同SRAM的数量。
文摘The protons in the secondary beam in the Beijing Electron Positron Collider（BEPC） are first analyzed and a large proportion at the energy of 50-100 MeV supply a source gap of high energy protons.In this study, the proton energy spectrum of the secondary beam was obtained and a model for calculating the proton single event upset（SEU） cross section of a static random access memory（SRAM） cell has been presented in the BEPC secondary beam proton radiation environment.The proton SEU cross section for different characteristic dimensions has been calculated.The test of SRAM SEU cross sections has been designed,and a good linear relation between SEUs in SRAM and the fluence was found,which is evidence that an SEU has taken place in the SRAM.The SEU cross sections were measured in SRAM with different dimensions.The test result shows that the SEU cross section per bit will decrease with the decrease of the characteristic dimensions of the device,while the total SEU cross section still increases upon the increase of device capacity.The test data accords with the calculation results,so the high-energy proton SEU test on the proton beam in the BEPC secondary beam could be conducted.
