Fabrication method of carrier-free semiconductor package

摘要

A carrier-free semiconductor package includes a circuit structure having an insulating layer and a circuit layer embedded in the insulating layer and having a plurality of conductive traces and RF (radio frequency) traces, a chip disposed on a first surface of the insulating layer and electrically connected to the conductive traces, an encapsulant covering the chip and the circuit layer, a ground layer formed on a second surface of the insulating layer opposite to the first surface, and a plurality of solder balls disposed on the conductive traces or terminals on the conductive traces, wherein portions of the solder balls electrically connect the ground layer so as to allow the RF traces and the ground layer to form a microstrip line having an RF function, thus obtaining a single-layer carrier-free semiconductor package having low cost and simplified RF design.

主权项

1. A fabrication method of a carrier-free semiconductor package, comprising the steps of:
forming on a carrier a circuit layer having a plurality of conductive traces and RF traces; forming an insulating layer on the carrier and the circuit layer, wherein the insulating layer has a plurality of openings for exposing the conductive traces, respectively, and has a first surface in contact with the carrier and a second surface opposite to the first surface; removing the carrier to expose the first surface of the insulating layer and the circuit layer; disposing a chip on the first surface of the insulating layer and electrically connecting the chip and the circuit layer; forming an encapsulant on the first surface of the insulating layer to cover the circuit layer and the chip; and forming a ground layer on the second surface of the insulating layer.