A structure for reduction of soft error rates in integrated circuits. The structure including: a semiconductor substrate; and a stack of one or more wiring levels stacked from a lowermost wiring level to an uppermost wiring level, the lowermost wiring level nearer the semiconductor substrate than the uppermost wiring level; and an alpha particle blocking layer on a top surface of the uppermost wiring level of the one or more wiring levels, the blocking layer comprising metal wires and a dielectric material, the blocking layer having a combination of a thickness of the blocking layer and a volume percent of metal wires in the blocking layer sufficient to stop a predetermined percentage of alpha particles of a selected energy or less striking the blocking layer from penetrating into the stack of one or more wiring levels or the substrate.