An integrated circuit device and a method of fabricating the same are presented. The integrated circuit device (1) includes two or more active components (30a, 30b), possibly fabricated by different semiconductor technologies, and an interposer structure (10) adapted for carrying the two or more active components such that at least one of the active components is carried on a top surface of the interposer structure. The integrated circuit device also includes at least one metal cap (40), furnished on the top surface of the interposer structure and encapsulating at least one of the active components. Some variants of the integrated circuit device of the invention are suited for operation under extreme conditions.