Sub-LET Threshold SEE Cross Section Dependency With Ion Energy

Abstract

This study focuses on the ion species and energy dependence of the heavy ion SEE cross section in the sub-LET threshold region through a set of experimental data. In addition, a Monte Carlo based model is introduced and applied, showing a good agreement with the data in the several hundred MeV/n range while evidencing large discrepancies with the measurements in the 10-30 MeV/n interval, notably for the Ne ion. Such discrepancies are carefully analyzed and discussed. Abstract-This study focuses on the ion species and energy dependence of the heavy ion SEE cross section in the sub-LET threshold region through a set of experimental data. In addition, a Monte Carlo based model is introduced and applied, showing a good agreement with the data in the several hundred MeV/n range while evidencing large discrepancies with the measurements in the 10-30 MeV/n interval, notably for the Ne ion. Such discrepancies are carefully analyzed and discussed.

Mechanisms of Electron-Induced Single-Event Latchup

“…First experimental evidence showing electron-induced SEL has been shown in this paper. The DUTs had a LET threshold of ∼ 3MeV cm 2 /mg [14]. It has been shown through simulation in [6] that electrons and photons are capable of producing nuclear interaction product with a LET of up to 13MeV cm 2 /mg and 15MeV cm 2 /mg, respectively.…”

“…A summary of the three memories can be seen in Table I. The Brilliance device has been characterized by both a heavy-ion beam and proton beams [12], [14], where they were referred to as SRAM F and BS62, respectively. The devices were biased through a programmable Agilent power supply, which was also used for delatching purposes.…”

“…In addition to the LET threshold, a more important value in terms of the cross section is the L 1% value, which is the so-called onset LET value or the value at which the cross section is 1% of the saturation cross section [16]. The value is 15 MeVcm 2 /mg for the Alliance memory [12], 6.5MeV cm 2 /mg for the ISSI memory [14] and 3.7MeV cm 2 /mg for the Brilliance. These values can also be seen in Table II.…”

“…To identify the effect that high-Z materials have on the energy deposited by HE electrons, protons, shown previously in [2], and photons in the sensitive volume (SV) of the SRAM, a FLUKA simulation was performed using a geometry described in [13] and [14] where it is shown to be representative of the SRAMs used in this paper. The geometry used in this paper is verified for the same components [13] for protons; as both protons and neutrons cause latchup events through a similar mechanism-silicon fragments caused by nuclear reaction with the Si atoms.…”

“…In addition, this phenomenon introduces a very strong cross section dependence with energy, therefore, requiting the need for testing at the maximum energy present in the working environment. In this paper, energy deposition simulations were made in FLUKA [10], [11] for electrons, using an integral rectangular parallelpiped (IRPP) geometry previously described in [12]- [14]. The geometry includes a layer of tungsten to show the effect of the electron-tungsten interaction recoils on the overall energy deposition cross section.…”