A methodology for a thin, flexible substrate having integrated passive circuit elements, and the resulting device are disclosed. Embodiments may include integrating one or more passive circuit components on a first or second surface of a substrate, and interconnecting one or more integrated circuit (IC) dies on a second surface of the interposer to the one or more passive circuit components with one or more metal-filled vias between the first and second surfaces, the first and second surfaces being opposite surfaces of the substrate.