Heavy-ion micro-beam use for transient fault injection in VLSI circuits

Summary form only given. The radiation exposure of electronic circuits and devices alters their electrical characteristics. When a high-energy particle hits a silicon substrate, and due to coulombian interaction, hole-electron pairs are created. A fraction of these carriers recombine but most of them are swept by the electric field in the depletion regions, generating current pulses that disrupt the normal operation of the circuit. As a consequence, this may lead to a very serious system failures, or progressive performance degradation. When critical missions use these systems, reliability is the main concern, therefore circuits with special considerations must be constructed using techniques for improving radiation tolerance as Radiation Hardening by Design (RHBD) that is cheap and fits well for designs implemented in sub-micron CMOS processes. To check circuit vulnerability of a hardened device different radiation tests must be conducted. For particle interaction tests, one of the most challenging tasks is to perform radiation ground tests that mimics real operation situations. Recently, many efforts have been achieved using laser equipments as in the works of Schwank¹ and Palomo² for transient fault injection, even though, the results must be correlated to heavy ion interaction to validate the approach. In this work, irradiation experiments with heavy-ions in VLSI circuits are reported. We explain how to lower the number of particles per second that reach the circuit, as also to focus the ion beam and control its position to hit on the desired place. We describe the dosimetry as also the measurement methodology. This work demonstrates that the use of a micro-beam line attached to a High-Energy accelerator is suitable for this kind of tests evidencing the validity and robustness of the method.