• • forming a first connection layer on a surface of the first conductive circuit disposed on the first groove by Electroless Nickel/Immersion Gold (ENIG), making the first connection layer electrically connected to the first conductive circuit;
  • disposing a conductive paste on a surface of the first connection layer away from the first conductive circuit to form a second connection layer, making the second connection layer electrically connected to the first connection layer; and putting the embedded element in the first groove, making the embedded element
  • be fixed to the inner layer assembly, and making the embedded element be electrically connected to the second connection layer.

Furthermore, the first insulating element and the second insulating element are formed by pressure buildup, the inner layer assembly comprises a first surface and a second surface disposed opposite to each other, the first groove does not extend to the second surface, the first opening penetrates the second surface and communicates with the first groove, the first insulating element covers the first surface and a surface of the embedded element away from the second surface, the second insulating element covers the second surface and contacts the embedded element through the first opening, the manufacturing method further comprising:

• • forming a first outer layer circuit on a surface of the first insulating element away from the second insulating element;