Integrated magnetics with closed-loop flux path

An integrated magnetics (IM) structure, comprising:

• a first magnetic layer;
• a second magnetic layer;
• a first dielectric layer disposed between the first magnetic layer and the second magnetic layer;
• one or more conductive layers etched to form patterned metal traces;
• wherein the patterned metal traces are embedded in the first dielectric layer;
• a first magnetic via;
• and
• a second magnetic via,
• wherein the first magnetic via is formed in a first hole that extends through the first magnetic layer, the first dielectric layer, and the second magnetic layer,
• wherein a first wall of dielectric material disposed in the first hole surrounds the first magnetic via,
• wherein the second magnetic via is formed in a second hole that extends through the first magnetic layer, the first dielectric layer, and the second magnetic layer,
• wherein a second wall of dielectric material disposed in the second hole surrounds the second magnetic via,
• wherein the first magnetic via, and the second magnetic via are disposed on opposite sides of at least a portion of the patterned metal traces,
• wherein a thickness of the first wall of dielectric material is configured to provide a level of voltage isolation between the first magnetic via and the patterned metal traces,
• wherein a thickness of the second wall of dielectric material is configured to provide the level of voltage isolation between the second magnetic via and the patterned metal traces,
• wherein each of the first magnetic via and the second magnetic via is configured to interconnect the first magnetic layer and the second magnetic layer, and
• wherein the patterned metal traces are configured, when electrical current flows through the patterned metal traces, to induce a magnetic flux through a flux path defined as a closed magnetic loop that traverses the first magnetic via, the first magnetic layer, the second magnetic via, and the second magnetic layer and encircles at least the portion of the patterned metal traces;
• wherein a magnetic paste fills each of the first hole and the second hole, and the magnetic paste is a mixture of epoxy and magnetic particles.