Structure with inductor embedded in bonded semiconductor substrates and methods

Abstract

Disclosed is a structure and a method of forming the structure. The structure includes first and second semiconductor substrates with adjacent surfaces (e.g., bonded surfaces), a first spiral-shape metallic feature in the first semiconductor substrate, and a second spiral-shaped metallic feature in the second semiconductor substrate. The second spiral-shaped metallic feature is aligned above and electrically connected to the first spiral-shaped metallic feature. In some embodiments, the second spiral-shaped metallic feature is stacked on and immediately adjacent to the first spiral-shaped metallic feature at the bonded surfaces, thereby forming a relatively large inductor with high Qin a relatively small area. In other embodiments, the first and second spiral-shaped metallic features are discrete inductors located on opposite sides of the semiconductor substrates from the bonded surfaces but electrically connected in parallel (e.g., using stacked TSVs), effectively forming a relatively large inductor with a high Qin a relatively small area.