1. A printed circuit board (PCB) laminated structure, comprising:a first substrate;
a second substrate disposed to overlap with the first substrate; and
an interposer assembly disposed between the first substrate and the second substrate and configured to allow signal communication between the first and second substrates,
wherein the interposer assembly comprises:
a housing configured to form a closed region between a top surface of the first substrate and a bottom surface of the second substrate;
a signal via electrically coupling the first substrate and the second substrate and configured to transmit signals between the first substrate and the second substrate; and
a ground via electrically coupled to the housing and configured to serve as a ground, wherein the ground via is positioned apart from the signal via by a predetermined distance, and
a metal coating layer disposed at a side surface of the housing and configured to shield signals, wherein the metal coating layer is selectively disposed along the side surface of the housing to be adjacent to signal emission devices mounted on the first and second substrates such that portions of the side surface of the housing are exposed between gaps of the selectively disposed metal coating layer.