Multilayer winding inductor

A multilayer winding inductor, comprising:

• an insulating layer disposed on a substrate;
• a first multi-level interconnect structure embedded in the insulating layer, comprising:
• a plurality of first looped conductive traces overlapping and separated from each other, each first looped conductive trace having a gap to define a first end and a second end separated therefrom by the gap;
• and
• a plurality of first conductive plugs disposed between the plurality of first looped conductive traces, electrically connecting the plurality of first looped conductive traces, wherein at least two first conductive plugs are disposed between the first ends of the neighboring first looped conductive traces and between the second ends of the neighboring first looped conductive traces, respectively;
• and
• a single-level interconnect structure disposed in the insulating layer and located over the first multi-level interconnect structure, comprising:
• an uppermost looped conductive trace having a gap to define a first end and a second end separated therefrom by the gap;
• and
• a second conductive plug disposed between the second end of the uppermost looped conductive trace and the first end of the first looped conductive trace adjacent thereto, to serve as an electrical connection between the first multi-level interconnect structure and the single-level interconnect structure.