# Mechanism and Equivalence of Single Event Effects Induced by 14 MeV Neutrons in High-Speed QDR SRAM
## 1 Introduction  
Atmospheric neutrons are produced by the interaction between high-energy cosmic radiation (including galaxy cosmic rays and solar wind) and the earth's neutral atmosphere [1], for example, the fluxes in atmospheric neutrons at the ground and 10 km flight height of Beijing city are 7.3 n/(cm\({}^{2}\cdot\)hr) and 1068 n/(cm\({}^{2}\cdot\)hr) [2], respectively. Atmospheric neutron-caused SEE in key ground electronics and avionics are becoming critical reliability issues because the smaller feature size of integrated circuits (IC) results in worse SEE characteristics [3; 4], resulting in data error, functional interrupt, or even the crash of the electronic system.  
Fourteen-nanometer FinFET devices have excellent performance, such as low power consumption, high integration and fast working speed; they have been gradually widely used in various electronic systems. Because the SEE-sensitive region and charge collection mechanism in FinFET devices are significantly different from the common planar devices, it is necessary to research the SEE in 14 nm FinFET devices.  
The 14 MeV deuterium-tritium neutron generators have gained increasing interest in evaluating the neutron-induced SEE sensitivity of modern ICs, with the advantages of great availability, low cost, and high efficiency (a large number of test boards can be arranged around the neutron target, thanks to the 4\(\pi\) distribution of generated 14 MeV neutrons). However, due to the clear difference between the energy spectrum of atmospheric neutron (meV-GeV) and 14 MeV neutron, the equivalence of 14 MeV neutrons for the evaluation of atmospheric neutron-induced SEE has been a hot topic in the community [5; 6; 7; 8; 9]. In 2013, [PERSON] et al. verified a 14 MeV neutron equivalence model based on the 90 nm SRAM process and found that the error range of the SEE cross-section induced by 14 MeV neutrons was less than two times [5]. In 2017, [PERSON] et al. studied the scope of 14 MeV neutrons for the evaluation of atmospheric neutron-induced SEE. It was found that the single event upset (SEU) cross-section is in good agreement, while more multiple-cell upsets (MCU) and single event latches (SEL) were induced by high-energy neutrons [6]. At present, controversy still exists about the equivalence of 14 MeV neutrons in various types of devices. Moreover, published work used the test results at the spallation neutron source as the golden reference. The neutron energy spectrum, flux, and incident direction of spallation neutrons are inconsistent with the real atmosphere case, resulting in the deviation of the experimental result. In this paper, for the first time, high-altitude real atmosphere test results are used to verify the 14 MeV neutron test results, and the underlying mechanisms are investigated by further Monte-Carlo simulations.  
In this work, the characteristics of SEUs and MCUs in high-speed QDR SRAM induced by 14 MeV neutrons are revealed and compared with a high-altitude real atmosphere test directly, based on our previous work on high-altitude tests [10], spallation source experiments [11] and \(\alpha\) particle experiments [12] of the QDR SRAM. Internal mechanisms are researched in more depth via Monte-Carlo simulations.