Integrated Circuits and methods for reducing thermal neutron soft error rate (SER) of a digital circuit are provided by doping a protection layer on top of the metal layer and in physical contact with the metal layer of the digital circuit, wherein the protection layer is doped with additional thermal neutron absorbing material. The thermal neutron absorbing material can be selected from the group consisting of Gd, Sm, Cd, B, and combinations thereof. The protection layer may comprise a plurality of sub-layers among which a plurality of them containing additional thermal neutron absorbing material.