Gamma-Ray Irradiation Induced Dielectric Loss of SiO2/Si Heterostructures in Through-Silicon Vias (TSVs) by Forming Border Traps

The performance of integrated circuits (ICs) deteriorates under irradiation. It is commonly believed that passive components in the IC such as through-silicon vias (TSVs) are insensitive to radiation damages. However, we find a counterexample by studying the effect of gamma-ray irradiation on a TSV, where its alternating current (AC) properties change significantly due to an emerging dielectric loss peak after irradiation, and the peak shifts toward lower frequencies at higher radiation doses. We propose a mechanism of the observed irradiation effect on the AC properties based on correlations between macroscopic and microscopic phenomena, and the emerging dielectric loss peak is attributed to the formation of a layer of border oxide traps (BTs). The defect-based analysis indicates that the AC dielectric loss due to gamma-ray irradiation is not restricted to TSVs but should also be applicable to other semiconductor devices with Si/SiO2 interfaces. Our work provides not only an approach for the quantitative characterization of BTs but also a practical approach to resist AC irradiation damage at the circuit or material level.