An integrated circuit device includes a substrate; an integrated circuit region on the substrate, said integrated circuit region comprising a dielectric stack; a seal ring disposed in said dielectric stack and around a periphery of the integrated circuit region; a trench around the seal ring and exposing a sidewall of the dielectric stack; and a moisture blocking layer continuously covering the integrated circuit region and extending to the sidewall of the dielectric stack, thereby sealing a boundary between two adjacent dielectric films in the dielectric stack.