An integrated circuit device package of this invention includes a flexible substrate having an upper patterned insulative layer, and a lower patterned conductive layer including a plurality of package leads. An integrated circuit die is fixed within a void of the upper surface of the flexible substrate. Electrical connections between the integrated circuit die and the package leads are provided. A rigid upper protective layer is present. The rigid upper protective layer encloses the integrated circuit die, and at least partially covers the top surface of the upper insulative layer. The semiconductor device package further comprises a rigid or semi-rigid metal lower protective layer opposite the upper protective layer including a ground plane proximal to the electrical leads and a power plane distal to the leads. Methods of production are also given.