Patent ID: 8633048

Claim:
A fabrication method of a package structure having micro-electro-mechanical system (MEMS) elements, comprising the steps of: preparing a plate having opposite first and second surfaces and preparing a wafer having opposite third and fourth surfaces, wherein the first surface of the plate has a plurality of first alignment keys, a plurality of recesses and a plurality seal rings disposed around peripheries of the recesses, and the third surface of the wafer has a plurality of MEMS elements, a plurality of electrical contacts and a plurality of second alignment keys; bonding the plate and the wafer together by aligning the first alignment keys of the plate with the second alignment keys of the wafer and disposing the seal rings on the third surface of the wafer such that the MEMS elements of the wafer are disposed in the recesses and enclosed by the seal rings of the plate; thinning the plate from the second surface thereof; forming on the second surface of the plate a plurality of third alignment keys corresponding to the second alignment keys of the wafer, respectively; forming a metal layer on the second surface of the plate; cutting the plate to form therein a plurality of openings exposing the electrical contacts and the second alignment keys; connecting the electrical contacts and the metal layer through a plurality of bonding wires; disposing a plurality of block bodies over the second alignment keys through an adhesive such that top surfaces of the block bodies are higher than the bonding wires; forming an encapsulant on the third surface of the wafer so as to encapsulate the plate, the electrical contacts, the block bodies and the bonding wires; partially removing the encapsulant, the bonding wires and the block bodies from a top surface of the encapsulant so as to expose one end of each of the bonding wires and the block bodies; and aligning through the second alignment keys so as to form on the encapsulant a plurality of metal traces electrically connected to the electrical contacts through the bonding wires.