Study of atmospheric muon interactions in Si nanoscale devices

Abstract

In this paper the impact of the muon radial ionization profile on Single-Event Upset (SEU) sensitivity for nanoscale technologies is investigated with simulations and experimental measurements. The physical model used in the simulation framework is compared with experimental measurements of the charge deposit induced by atmospheric particles on a CCD pixel array. This scientific instrument is used to monitor the atmospheric muons, and allows to investigate the charge deposition induced by muon of micrometric sensitive volumes (i.e. the CCD pixel). Atmospheric and underground sites are considered for monitoring pixel-charge events and the combined analysis of the data is used to discriminate muons from other particles. 3D descriptions of muon tracks were simulated with radiation transport code Geant4, and coupled with Single Event Effect (SEE) simulation based on multi-physics approaches (MUSCA SEP3) to investigate the SEU cross-section and Soft Error Rate (SER) trends as function of technological downscaling. SER trends are analyzed for bulk technologies, from 65 to 14 nm integration nodes, in both ground and avionic environments. Results show that for technologies whose characteristic lengths are greater than 50 nm, it is not necessary to consider radial energy deposit structure of muon in SEE assessment. At ground, downscaling of the technological node induces an increase in the SEU susceptibility to cosmic ray showers, mainly because of muons. For nanoscale devices operating at avionic altitude, the muon contribution to the SER is very weak in comparison of the proton and neutron contributions.