Abstract
<P>PROBLEM TO BE SOLVED: To provide a 3D electronic packaging structure having grounding performance enhanced and a built-in antenna. <P>SOLUTION: A packaging unit 300 can achieve multi-chip stacking through signal contacts 302, 314, 315, and 316 on the upper and lower surfaces of the unit. A single or a plurality of grounding layers 311 are set on the back of the substrate in the packaging unit 300 to facilitate the grounding for the semiconductor element and are applied to a wafer level packaging process. The grounding layer 311 is a signal transmission path of the electronic element. Moreover, a single or a plurality of via-holes around the electronic element layer 313 permit electrical signal connection between the upper and lower surfaces of the packaging structure and enable more functionality of the packaging unit 300. Moreover, the grounding layer 311 can have circular signal channels for constituting a 3D-stacked packaging structure with a built-in antenna.