应用中国散裂中子源9号束线端研究65 nm微控制器大气中子单粒子效应

Atmospheric neutron single event effect in 65 nm microcontroller units by using CSNS-BL09

采用设置和不设置镉中子吸收体两种方式,利用中国散裂中子源9号束线(CSNS-BL09)对65 nm微控制器进行了大气中子单粒子效应辐照测试.测试中探测到的效应主要为单位翻转.测试结果表明,对于该款微控制器,热中子引起的中子单粒子翻转占比约65%;进一步分析表明,热中子与10B反应产生的0.84 MeV7Li可能是诱发微控制器单粒子翻转的主要因素.

The 65 nm-microcontroller units(MCUs) are being widely used in critical terrestrial tests, and the risk from atmospheric neutron becomes more and more serious. The spallation neutron source contains broad energy spectrum, which is different from the mono-energetic neutron sources, and is the most ideal irradiation source for atmospheric neutron single event effect(SEE). Benefiting from China Spallation Neutron Source(CSNS),the atmospheric neutron SEE in 65 nm-MCUs is tested for the first time at the CSNS 9th beam line in China.The beam line is locatedin the 46° direction along the proton hitting the target, and the neutron spectrum is achieved to range from meV to 1.6 GeV. The test is conducted in two conditions in order to investigate the influence of thermal neutron. One is that the thermal neutrons are shielded with a 2-mm-thick cadmium slat at the beam ejection hole, and the other is not. The detected effects are single bit upset(SBU) events. 16 SBU events are detected when 5.3363 × 1017 protons hit the tungsten target without the thermal neutron, and 63 SBU events are recorded in the condition of 7.2131 × 1017 protons striking the target and thermal neutrons included. Comparing with the high energy neutron(>1 MeV), the SBU events caused by thermal neutron contribute about 65% of the number of total upset events. The test results preliminarily illustrate that the thermal neutrons dominate the 65 nm MCU reliability.